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Will Core Duo Notebooks Trade Battery Life For Quicker Response?
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1. Is Faster Notebook Performance Worth Shorter Battery Life?

Just about a year after Intel introduced the second generation Centrino Mobile Technology with Sonoma, its next generation "Napa" implementation is now ready for the light of day. Sonoma was designed to make desktop PC features - such as PCI Express, Serial ATA, and dual channel DDR2 memory - available for use in notebooks.

In contrast, Napa represents a move to a completely new hardware base. This paves the way for a completely new era in mobile computing: From now on, notebooks can double their "brain power", by using CPUs with two independent processing units, a technology commonly known as Dual Core processors. A primary advantage of CPUs with two cores comes from their ability to handle two or even more multiple tasks simultaneously. This means that while one processing unit might be busy with conducting a virus scan, for example, the second unit will still be available to handle other tasks. As a result, long delays - which can amount to seconds when switching from one application to another when multiple concurrent programs are working - are supposed to become a thing of the past.

According to vendor reports, the battery life for the new dual core platforms in notebooks using Intel's integrated graphics core isn't supposed to decline at all, when compared with the previous generation (Sonoma). Our first measurements on a prototype device with a dedicated graphics chip (ATI X1600) paint a completely different picture, however, and this detracts from the positive impression that the new technology's improved performance creates. We can only guess whether the relatively modest battery lifetimes we observed in our test system are due to the graphics subsystem, the chipset itself, or a combination of these elements. That said, as we'll prove later in this article, this new CPU is definitely no energy hog.

Like the old platform, this new one is designated using the Intel Centrino Mobile Technology brand name, as long as the device includes a single core CPU along with a new Intel chipset and an Intel WLAN module. If system builders use a WLAN module from a supplier other than Intel, the device may not use the Centrino name and Intel's marketing incentives and promotions diminish considerably. Notebooks that use a dual core processor (along with a corresponding new Intel chipset and WLAN module) are instead designated as Intel Centrino Duo Mobile Technology.

Say goodbye to the old familiar processor designation "Pentium M" and the various related model designations such as the "Pentium M xxx". The latest Intel naming scheme uses a five-element alphanumeric code that takes the form "Axxxx". In addition, product names now are the Intel Core Duo Processor and Intel Core Solo Processor; you'll read more about these later in this story.

2. Yonah: Pentium M Successor With Two Cores

65 nm manufacturing makes it possible: Yonah has two cores and noticeably more transistors, but the die is barely larger than that of a Dothan processor.

Like the current desktop dual core models in the Pentium D 900 series, Yonah technology is based on the 65 nm fabrication process. Among other things, when compared to the preceding Dothan models, this die shrink enables placing more transistors into the same surface area. This helps reduce some production costs, because more CPU dies can be engraved onto a single wafer than would have been possible with older process technology.

Together, both of Yonah's cores consume a surface area of only 90.3 mm2, including a 2 MB L2 cache, with a total transistor count of 151 million. The die is only slightly larger than the preceding single core Dothan, which included approximately 140 million transistors on a surface area of 83.6 mm2.

Still, one shouldn't overlook that more than 90 percent of Dothan's transistors went into its L2 cache alone. Had Intel's Yonah or the Pentium D 800 desktop models been constructed using 90 nm technology, not only would the 2 MB L2 cache have been about 40 percent larger, but both of the processor cores would have been bigger as well. This would also have entailed power consumption levels high enough to make their use in a mobile PC difficult, if not impossible. The use of 65 nm technology makes it possible to fabricate a dual core processor whose theoretical maximum power consumption is 31 Watts, only 4 Watts higher than the Pentium M 780's at 27 Watts.

Despite identical pin counts, Dothan and Yonah are not pin-compatible.
3. ..., Faster Front Side Bus (FSB),

Two cores automatically entail more memory access. To prevent the Front Side Bus (FSB) in these new CPUs from becoming a bottleneck, Intel raised the FSB clock rate from 133 MHz to 166 MHz in this latest incarnation. Since Intel deploys a quad data rate protocol, four data transfers occur per cycle, resulting in speed designations of FSB533 and FSB667. That increase boosts maximum FSB bandwidth from 4.2 GB/s to 5.3 GB/s. This is still well below the maximum memory bandwidth of 10.76 GB/s possible for DDR2-667 dual channel memory technology.

The Intel Core Duo T2500 processor runs at a maximum clock rate of 2 GHz (HFM, or Highest Frequency Mode).

As a consequence of this improvement, installing DDR2-667 RAM in a Centrino Duo system removes the chances of the CPU being required to wait on memory for data delivery. Strictly speaking, DDR2-533 RAM, with a maximum bandwidth of 8.5 GB/s, is already sufficient to meet the needs of fast FSB667 in the dual core CPU. You should thus not worry if you look at a brand-new Yonah system and find it outfitted with DDR2-533 SO-DIMMs - faster DDR2-667 modules are more expensive and won't boost performance measurably.

Platform Processor Bus Speed Memory Speed Memory Configuration
Napa 5.33 GB/sec 10.67 GB/sec
8.53 GB/sec
5.33 GB/sec
4.26 GB/sec
DDR2-667
DDR2-533
DDR2-667
DDR2-533
(Dual-Channel)
(Dual-Channel)
(Single-Channel)
(Single-Channel)
Sonoma 4.25 GB/sec 8.53 GB/sec
6.40 GB/sec
4.26 GB/sec
3.20 GB/sec
2.66 GB/sec
DDR2-533
DDR2-400
DDR2-533
DDR2-400
DDR-333
(Dual-Channel)
(Dual-Channel)
(Single-Channel)
(Single-Channel)
(Single-Channel)

However, this situation looks a little different when a Centrino Duo system uses a graphics core that is integrated into the chipset, instead of a graphics chip with its own dedicated video memory. In that case, the CPU and the integrated graphics core must share memory bandwidth, a technology known as Unified Memory Architecture (UMA), sometimes also called shared memory architecture. This requires allocating an appreciable portion of memory bandwidth to handling video data. In notebooks with shared memory graphics, therefore, you should insist on faster DDR2-667 memory modules.

4. ...and Other Important Enhancements

Intel wouldn't be Intel if it didn't garnish the introduction of a new CPU model series with a bundle of new marketing buzzwords. In the pages that follow we'll shed light on these new terms:

  • Smart Cache, Dynamic Cache Allocation
  • Dynamic Power Coordination
  • Digital Media Boost
  • Intel Advanced Thermal Management
Smart Cache: Cache As Much As You Can

In contrast to the dual core CPUs in the Intel Pentium D 900 series for desktop PCs, the new mobile dual core processors include two independent processor units that share a single 2 MB L2 cache. Both sit on the same die, and both use the same front side bus to access the chipset, the L2 cache, and communicate with each other. Intel calls this shared 2 MB L2 cache "Smart Cache".

Smart Cache Architecture of the Core Duo processors, aka Yonah

In the Pentium D 900 desktop processors, on the other hand, each core has its own 2 MB L2 cache, with each pair (core and cache) residing on its own die, though both dies interconnect with each other using the front side bus.

Split Cache Architecture in the Pentium D 900

What advantages does the Core Duo's Smart Cache architecture on the Yonah processor enjoy when compared to split-cache variants, like those found in desktop processors such as the Pentium D 900? Well, assume for example that both CPUs are working in parallel on the same task, such as on image filtering in Photoshop. In that case, it's important for both cores to be aware of where current, valid data entries reside in the L2 cache, and to know if such entries must be loaded from the system RAM instead - a process that takes considerably longer to complete than cache access. Both cores need to make sure they're working together and not at cross purposes to get things done quickly, and make sure that core 1 won't overwrite data that core 2 has already worked on.

A shared L2 cache, in connection with a shared FSB, implements a kind of high-speed link between the cores right on the chip. In addition, this architecture/design (two cores with a single shared L2 cache) reduces the amount of FSB traffic, which in turn has a positive impact on both energy consumption and overall performance. In a split-cache design, on the other hand, information exchange between the two cores involves determining whether current valid data resides in the other L2 cache or in RAM; either of these involves time-consuming transfers across the FSB.

When used in tandem with Dynamic Cache Allocation, the number of cache misses when compared to a split-cache design should be noticeably lower, in keeping with the motto, "Cache as much as you can." In this context, Dynamic Cache Allocation means that each of the two cores always uses as much of the 2 MB L2 cache as the running applications allow. In other words, there's no fixed limit on cache allocation for either core. In addition, Intel core processors can turn off the power to unused portions of the L2 cache based on workloads in execution, thereby saving energy. This artful dodge does not affect data integrity in the L2 cache either.

5. Dynamic Power Coordination

As in the predecessor Banias and Dothan CPUs, these new processors can adjust core voltages and clock frequencies to meet changing application performance demand. Previously, this energy saving mechanism had been called Enhanced SpeedStep, but it had to be reworked and improved for the new dual core architecture. Intel describes this enhanced implementation with the catchphrase "Dynamic Power Coordination".

In this technique, the clock rate and core voltage applied to both cores is determined by the core that currently services the heaviest demand. If core 1 runs at 2 GHz, the other core runs at the same speed and voltage level, regardless of whether that core is executing some task or is idle. Only when core 1 reduces its clock rate can core 2 switch down to the same SpeedStep performance mode, assuming of course, that core 2 has no more to do than core 1 at that particular instant.


Dynamic Power Coordination

As just described, transitions from one SpeedStep performance mode to another are coordinated between the cores. This situation changes when both CPU cores are only minimally loaded and running at the minimal core clock rate. Intel designates this situation as "Lowest Frequency Mode", or "LFM".

The technical literature for the processor assigns these various performance and energy consumption levels using alphanumeric codes that run from C0 to C4. When the situation that produces LFM occurs, the general power management algorithm keeps core 1 active at the C0 level, but turns off the clock in core 2. This puts core 2 into the power-saving C2 level. If both cores are in Deep Sleep Mode (C3), the CPU (both cores) can be turned down further into DeeperSleep (C4) or even into Enhanced Deeper Sleep (DC4) modes.

It's not possible, however, for core 1 to be set to DC4, or perhaps C1, C2, or C3, and for core 2 to operate at maximum frequency at the same time. The overall voltage regulator simply won't permit this to occur. In so-called Enhanced Deeper Sleep mode, Yonah actually won't copy unused cache lanes back to system memory; it turns the L2 cache off entirely and lowers core voltage still further from levels set for Deeper Sleep Mode. This definitely helps conserve power.

6. Dynamic Power Coordination, Continued

The Intel Core Duo Processor T2500 runs at a maximum of 2 GHz (HFM)

The clock speed for Lowest Frequency Mode (LFM) for Yonah CPUs is 1,000 MHz, whereas it was 800 MHz for Dothan processors. This implies no technical change, simply reflecting the fixed multiplier that applies to the front side bus. For all Banias, Dothan, and Yonah processors, this takes a value of 6. The Highest Frequency Mode (HFM) varies by Core Duo Processor model, ranging from 1.5 GHz (Core Duo Processor LV L2300) to 2.16 GHz (Core Duo Processor T2600).

The minimum CPU clock rate for Intel Core Duo processors in the Yonah series is 1 GHz (LFM).

The following table briefly summarizes the differences among the various Centrino CPUs.

Intel Banias Intel Dothan Intel Yohna AMD Turion 64
Clock 1.00 - 1.70 GHz 1.20 - 2.26 GHz 1.50 - 2.16 GHz 1.60 - 2.20 GHz
L2-Cache 1 MB 2 MB 2 MB 512 kB / 1 MB
Process 130 nm 90 nm 65 nm 90 nm
FSB 400 400/533 667 400
64 Bit no no no yes
7. Digital Media Boost

Intel uses the name "Digital Media Boost" to refer to a variety of new features, including the addition of the SSE3 instruction and accommodations for larger floating point numbers. According to Intel, these capabilities should speed up the playback and rendering of digital content, and thus lead to a better multimedia experience on suitably-equipped PCs.

CPU Instructions
Intel Core Duo MMX, SSE, SSE2, SSE3
Intel Dothan MMX, SSE, SSE2
AMD Turion 64 MMX, 3DNow!, SEE, SSE2, SSE3, x86-64
Intel Advanced Thermal Management

Compared to its predecessors, thermal monitoring and management for Core Duo processors has been refined.

Every working subsystem inside the Core Duo processor has its own thermal monitor and a temperature sensor near all known hot spots. The legacy thermal diode - which is intended to prevent a CPU from self-destructing should the die overheat too much as a result of a failed or defective CPU fan - is shared between both cores. Because each core makes a separate temperature sensor available, it is theoretically possible to regulate the speed of the CPU fan more precisely; this is due to the paramount importance of die temperature in regulating the cooling system. As a consequence, Yonah notebooks should run more quietly and last longer.

8. I've Got A Core Duo Processor LV L2400. What Have You Got?

Before we get into a discussion of the Mobile 945 Express chipset family, we must first sort out the often-difficult problems involved in understanding Intel's new model designations. In May of 2004, after careful consideration, Intel presented its "popular" processing numbering scheme to the mobile PC scene. At that time, Intel let us know that it would also be doing away with mention of cache size, architecture, FSB speed, and other technologies such as Hyper Threading in its product designations. The result was a set of triple-digit numeric codes. The first digit designated the processor classification; 9, 8 and 7 stood for high end, 6 and 5 for middle-class, and 3 referred to entry-level segment CPUs.

Intel has "simplified" its model designations for new CPUs by imitating the standard that AMD set with its Turion 64 model numbering scheme. The new Intel mobile CPU models in the Core Duo and Core Solo series are identified using an alphanumeric code that starts with a character prefix and is followed by a four-digit numeric code.

The letter immediately establishes the power classification, and is thus a metric for how much power the CPU "uses". There are three power classifications: U, L, and T. Those who now believe that these letters represent a definite relationship between power classifications and terms like ultra low voltage, low voltage, and something like temperature are wrong. Intel has officially disclaimed any direct relationship or easy translations for these designations.

Lately, when I find myself considering such matters, I can't help but ask why they don't just call these things something like "Doesn't mean anything 2600" perhaps abbreviated as DMA2600, or even just XYZ2600, instead. The value of the following four-digit number in the new Intel product model codes is likewise a measure of the "performance-related" configuration characteristics of the CPU. The whole shebang looks something like this:


To the buyers in electronics markets around the world, and to technical types everywhere, we wish much joy and success at deciphering the new Intel CPU model codes in the sales pitches they must endure. ;-)

9. Models And Pricing For Core Duo And Core Solo CPUs
Processor Processor Number Core Clock Price 1k unit
Intel Core Duo Processor T2600 Dual 2.16 GHz $637
Intel Core Duo Processor T2500 Dual 2.00 GHz $423
Intel Core Duo Processor T2400 Dual 1.83 GHz $294
Intel Core Duo Processor T2300 Dual 1.66 GHz $241
Intel Core Solo Processor T1300 Single 1.66 GHz $209
Intel Core Duo Processor LV L2400 Dual 1.66 GHz $316
Intel Core Duo Processor LV L2300 Dual 1.5 GHz $284

Intel is starting with the introduction of seven new CPU models. The Core Solo Processor T1300 in this current line-up represents Intel's only single-core Yonah processor. On the die, however, the Core Solo T1300 includes two independent processing units (cores), one of which Intel turns off during the chip validation process.

What Intel has now that it never had before is a dual core ultra low voltage processor, intended specifically for use in ultra portable notebooks. This is an area where recent experience makes us believe a performance boost could be especially beneficial. That's because ultra portable notebooks and Tablet PCs bog down too often by virtue of the weak processor performance our testing has revealed, which makes them into what can only be described as slick but expensive portable typewriters. The two low voltage models, L2400 and L2300, presumably aim directly at the ultra light mobile PC market. With maximum power consumption that's probably somewhat over 10 W, they must be actively cooled under all circumstances. Of course, this requires more energy still, and also has an impact on their overall noise level.

10. Overview Of All Centrino Generations
Intel 945PM/GM (Yohna Processors)
Processor Coreclock L2-Cache Frontsidebus Die Power (TDP)
Core Duo T2600 Dual 2.16 GHz 2 MB 667 MHz 65 nm 31 W
Core Duo T2500 Dual 2.00 GHz 2 MB 667 MHz 65 nm 31 W
Core Duo T2400 Dual 1.83 GHz 2 MB 667 MHz 65 nm 31 W
Core Duo T2300 Dual 1.66 GHz 2 MB 667 MHz 65 nm 31 W
Core Solo T1300 1.66 GHz 2 MB 667 MHz 65 nm 27 W
Core Duo LV L2400 Dual 1.66 GHz 2 MB 667 MHz 65 nm 15 W
Core Duo LV L2300 Dual 1.50 GHz 2 MB 667 MHz 65 nm 15 W
Intel 915PM/GM (Dothan Processors)
Pentium M 780 2.26 GHz 2 MB 533 MHz 90 nm 27 W
Pentium M 770 2.13 GHz 2 MB 533 MHz 90 nm 27 W
Pentium M 760 2.00 GHz 2 MB 533 MHz 90 nm 27 W
Pentium M 750 1.86 GHz 2 MB 533 MHz 90 nm 27 W
Pentium M 740 1.73 GHz 2 MB 533 MHz 90 nm 27 W
Pentium M 730 1.60 GHz 2 MB 533 MHz 90 nm 27 W
Pentium M 758 LV 1.50 GHz 2 MB 400 MHz 90 nm 10 W
Pentium M 753 ULV 1.20 GHz 2 MB 400 MHz 90 nm 5 W
Celeron M 370 1.50 GHz 1 MB 400 MHz 90 nm 21 W
Celeron M 373 ULV 1.00 GHz 512 kB 400 MHz 90 nm 5 W
Intel 855PM/GME (Dothan/Banias Prosessors)
Pentium M 765 2.10 GHz 2 MB 400 MHz 90 nm 21 W
Pentium M 755 2.00 GHz 2 MB 400 MHz 90 nm 21 W
Pentium M 745 1.80 GHz 2 MB 400 MHz 90 nm 21 W
Pentium M 735 1.70 GHz 2 MB 400 MHz 90 nm 21 W
Pentium M 725 1.60 GHz 2 MB 400 MHz 90 nm 21 W
Pentium M 715 1.50 GHz 2 MB 400 MHz 90 nm 21 W
Pentium M 705 1.50 GHz 1 MB 400 MHz 130 nm 24.5 W
Pentium M 738 LV 1.40 GHz 2 MB 400 MHz 90 nm 10 W
Pentium M 718 LV 1.30 GHz 1 MB 400 MHz 130 nm 12 W
Pentium M 733 ULV 1.10 GHz 2 MB 400 MHz 90 nm 5 W
Pentium M 723 ULV 1.00 GHz 2 MB 400 MHz 90 nm 5 W
Pentium M 713 ULV 1.10 GHz 1 MB 400 MHz 130 nm 7 W
Celeron M 360 1.40 GHz 1 MB 400 MHz 90 nm 21 W
Celeron M 350 1.30 GHz 1 MB 400 MHz 90 nm 21 W
Celeron M 340 1.50 MHz 512 kB 400 MHz 130 nm 24.5 W
Celeron M 330 1.40 GHz 512 kB 400 MHz 130 nm 24.5 W
Celeron M 320 1.30 GHz 512 kB 400 MHz 130 nm 24.5 W
Celeron M 310 1.20 GHz 512 kB 400 MHz 130 nm 24.5 W
Celeron M 353 ULV 900 MHz 512 kB 400 MHz 90 nm 5 W
Celeron M 333 ULV 900 MHz 512 kB 400 MHz 130 nm 7 W
LV = Low Voltage, ULV = Ultra Low Voltage

With new CPUs and a new platform there must naturally also be new logos, which borrow from the form and color of the new Intel logo.

This is the new Intel logo.

Yes, you read that correctly. On January 3, 2006, Intel changed all its product logos as well as its corporate motto. After 14 years of Intel "Inside" on all Intel-based PCs, the new slogan henceforth is Intel, "Leap Ahead". Yet the question is: Does the firm know where it is leaping?


The Core Solo Processor logo

The Core Duo Processor logo

The Centrino Duo Mobile Technology logo

The new and improved Centrino Mobile Technology logo
11. New Chipsets And Two Different Southbridges

It isn't possible to tell which of the two Southbridge components actually resides in a notebook just by looking at the case. We have to believe, however, that as a rule the base ICH7M Base (82801 GBM) version will be installed in most such devices. That's because the additional RAID functionality of the more sophisticated Southbridge costs more money, and comes into play only for a very few notebook PCs. This ignores the 17" multimedia monsters with two hard disks for the moment, because they're more likely to show up in the living room than in the office anyway.


Could Intel be planning a Napa Extreme Edition for notebook PCs?

WLAN Modules Take PCI Express Mini Card Form

The new wireless LAN module is smaller and uses the PCI Express bus.

The 3945ABG (Golan) is the first Intel WLAN module that connects to the system using the PCI Express bus rather than the plain-vanilla PCI bus. The most noticeable thing about the 3945ABG module is its dimensions: at 1.181" x 2.01" (30 x 51 mm) it's visibly smaller than earlier such components. In fact, PCI Express Mini Cards are only about half the size of classic Mini PCI Cards.

To conform to the specification, a PCI Express Mini Card socket in a notebook must support both an x1 PCI Express link and a USB 2.0 link. The Express Mini Card itself may use the x1 PCI Express link, the USB 2.0 link, or both links to communicate with the system. By contrast, the substantially larger ExpressCard socket requires that the socketed device link to the PCI Express bus.

Old vs. New: Taken together, the new components require noticeably less space in a notebook.

As did its predecessor, the 2915ABG, the 3945ABG module transmits using the well-known IEEE-802.11 a, b, and g standards. When used with Cisco access points (APs), the new unit is supposed to be able to load-balance communication among individual APs inside the broadcast range of the notebook, thereby increasing data throughput. The vendor claims that this also improves immunity to external interference, while reducing the amount of interference this device itself produces when compared to preceding models.

WPA2 and Cisco Extension V4 support are also built in, and the user interface for the Pro Wireless Software has been completely reworked. Intel couldn't yet substantiate for us whether the card actually supports wake-on-LAN as promised, and under which circumstances this feature actually works in practice. Pairing up Cisco AP softphone applications with the 3945ABG module is also supposed to improve voice quality, through the prioritization of bandwidth for VoIP calls.

12. Test System Configuration Details And Comparison Systems

We used an Asus A6JA for testing, thanks to a loan from this early adopter of Intel's new Centrino Duo Mobile Technology. Along with an Intel Core Duo T2500 (2.00 GHz) processor, this machine also includes a 15.4" TFT display, two 512 MB DDR2-533 memory modules, and the 945PM Express chipset. ATI's high end graphics chip - the Mobility Radeon X1600 - works in tandem with 512 MB of dedicated video RAM to handle video data.

To compare the Centrino Duo to a Centrino single (older model) we selected the LG Electronics LW60 Express. This is one of the fastest 15.4" Sonoma notebooks, and also belongs in the second generation of Centrino components. LG's LW60 Express includes a Pentium M 760 (2.00 GHz) and two 512 MB DDR2 memory modules that operate in dual channel mode. To determine if the Intel Core Duo T2500 runs faster than the fastest Pentium M currently available - the Pentium M 780 (2.26 GHz) - we also conducted a handful of measurements with this processor in the LW60 as well.

HP's nx6125 represented the AMD faction, which we outfitted with a Turion 64 ML-40 and 1 GB of DDR333 memory. For those who don't already know, the integrated memory controller in the Turion 64 CPU supports neither energy saving DDR2 RAM nor faster dual-channel mode operation. This unit uses an ATI Mobility Radeon X300 integrated into the chipset, which offers sufficient performance for most standard applications.

System Hardware
Intel Pentium M 780 LG LW60 - JDPG
Intel Pentium M 760 ATI Mobility Radeon X600 - 128 MB
2x 512 MB DDR2-533 (CL 4.0-4-4-15)
Intel Core Duo T2500 Asus A6000 - A6JA
ATI Mobility Radeon X1600 - 512 MB
2x 512 MB DDR2-533 (CL 4.0-4-4-15)
AMD Turion 64 ML-40 HP nx6125
ATI Mobility Radeon X300 - 128 MB
2x 512 MB DDR333 (CL 2.5-3-3-7)
System Software & Drivers
OS Windows XP Professional 5.10.2600, Service Pack 2
DirectX Version 9.0c (4.09.0000.0904)
Graphics Driver notebook manufacturer
Chipset Driver notebook manufacturer
13. Benchmarks And Settings

The table provides an overview of the benchmarks used, and their associated settings.

Benchmarks and Settings
Video
Pinnacle Studio 10 Plus Version: 10.1.2.2150
from: 352x288 MPEG-2 41 MB
to: 720x576 MPEG-2 95 MB
Encoding and Transition Rendering to MPEG-2/DVD
no Audio
TMPGEnc 3.0 Xpress Version: 3.0.4.24 (no Audio)
182 MB VOB MPEG2-source (704x576) 16:9
DivX 6.1 Version: 6.1 (4 Logical CPUs)
Profile: High Definition Profile
Multipass, 3000 kbit/s
Encoding mode: Insane Quality
Windows Media Encoder Version: 9.00.00.2980
Windows Media Video 9 Advanced Profile
720x480 AVI to WMV (426 MB)
320x240 (29.97 fps)
282 kbps streaming
Applications
AVG Anti-Virus 7.1 Version: 7.1.0.352 (File)
Version: 7.1.362 (Program)
(3.85 GB, 14.007 Files, 1.177 Folders)
ABBYY FineReader Version: 8.0.0.714 Pro Part#4591
convert PDF to DOC
950 pages Book "War and Peace" PDF-Version
Adobe Photoshop CS 2 Version: 9.0
VT-Runtime Script
Rendering from 5 Pictures (66 MB, 7 Filters)
Autodesk 3D Studio Max Version: 8.0
Modell "Stadium"
6 Frames HTDV 1920 x 1080
Applications (Multitasking)
Multitasking I Winrar (181 MB, 23 Files, 1 Folder)
Lame (10:41 Minutes)
Multitasking II Winrar (181 MB, 23 Files, 1 Folder)
Lame 3.97 Beta 2
Ogg (10:41 Minutes)
WMV (720x480, 32 Sec)
Multitasking III Finereader (50 Pages PDF-Book)
AVG Anti-Virus (3.85 GB, 14.007 Files, 1.177 Folders)
Mobile Mark 2005
DVD playback 2005
InterVideo WinDVD 6.0
Wireless browsing 2005
Microsoft Internet Explorer 6.0
Mobile Mark 2005
Office productivity 2002SE
Adobe Photoshop 6.0.1
Netscape Communicator 6.0.1
Macromedia Flash 5.0
Microsoft Word 2002
Microsoft Excel 2002
Microsoft PowerPoint 2002
Microsoft Outlook 2002
McAfee VirusScan 5.13
WinZip 8.0
Mobile Mark 2005
Reader 2002SE
Netscape Communicator 6.01
Sysmark 2004 SE
Internet Content Creation
Adobe After Effects 5.5
Adobe Photoshop 7.01
Adobe Premiere 6.5
Discreet 3ds max 5.1
Macromedia Dreamweaver MX
Macromedia Flash MX
Microsoft Windows Media Encoder 9 Series
McAfee VirusScan 7.0
WinZip 8.1
Sysmark 2004 SE
Office Productivity
Adobe Acrobat 5.0.5
Microsoft Access 2002 SP-2
Microsoft Excel 2002 SP-2
Microsoft Outlook 2002 SP-2
Microsoft PowerPoint 2002 SP-2
Microsoft Word 2002 SP-2
Microsoft Internet Explorer 6.0 SP1
ScanSoft Dragon NaturallySpeaking 6 Preferred
McAfee VirusScan 7.0
WinZip 8.1
Synthetic
SiSoftware Sandra 2005 Version 2005.7.10.60 SR2
CPU Test = MultiMedia / CPU Arithmetic
Memory Test = Bandwidth Benchmark
14. Extended Benchmark Suite

Along with the typical THG notebook tests we normally run, such as MobileMark 2005 and SYSmark 2004 SE, we added a few additional applications that feature code optimized specifically for dual core CPUs. We also used some relatively simple techniques to create three distinct multi-tasking scenarios that involve running various applications.

The first and third scenarios (Multitasking I/III) both run two applications in parallel, while the second (Multitasking II) runs four applications in parallel. Courtesy of a home-grown tool, we can measure how long it takes for a test system to complete all tasks. The results from this homebrew test serve as a convincing demonstration of dual core system advantages.

In the following pages, we'll describe briefly which applications we used in our testing, and how we combined various applications in our three multitasking scenarios.

Pegasys TMPGenc 3.0 Xpress, Div X6.1

TMPGenc 3.0 can transcode various DVD video object files into MPEG-4 format. We also used a multicore-optimized version of DivX 6.1 to help complete this task.

Adobe Photoshop CS 2

By basing itself on Virtual Run Time, our script simulates real-time user activities in Photoshop CS 2. A total of seven images (66 MB) are opened, and seven different filters applied. Three of the filters are thread optimized, and the application itself is also optimized for dual core processors.

Grisoft AVG Virus Scan 7.1

We used this antivirus program to scan the installation directory for SYSmark 2004 SE for viruses. To obtain stable and reproducible results, it's essential to perform a preliminary scan before taking any measurements. That's because Windows caching features come into play only in the second run-through - they're read from disk into cache during the first run, and remain available from cache during the second run - which of course affects related test measurements. This trick prevents hard disk access times from imposing a measurable effect on the results measured. AVG Virus Scan isn't optimized for dual core processors, but when used simultaneously with another program such as FineReader 8, such usage illustrates an advantage for dual core systems nonetheless.

15. ABBYY FineReader 8

We used FineReader 8 to convert the PDF version of Leo Tolstoy's classic tome War and Peace into MS Word DOC format. When set to Background Recognition mode, the most current version of this program (8) supports using both processing units independently in a dual core CPU.

Windows Media Encoder

Using Windows Media Encoder 9, we converted a 426 MB AVI file into WMV format. The Windows Media Encoder is well-known to be optimized for use in dual core systems.

Autodesk 3D Studio Max

We used this application to open a 21 MB project file named "Stadium" at the same time that we took 6 images and rendered them into a short slide show at HDTV resolution. This application is also optimized for dual core processors.

Pinnacle Studio 10 Plus

Using the multi-core equipped Pinnacle Studio 10 Plus application, we scaled a video file from its native 352x288 MPEG-2 format into a 720x576 MPEG-2 version, while also applying various filters to the resulting output.

Multitasking I

Our first multi-tasking scenario used a script to execute WinRAR and the Lame MP3 encoder in parallel. As the CPU was put to work converting a 108 MB WAV file into MP3 format using Lame, it also had to run WinRAR on a 181 MB folder containing 23 files to create an archive with maximum compression.

Multitasking II

This scenario represents a more demanding reworking of the preceding scenario. Along with WinRAR and Lame, we added Ogg Vorbis and the Windows Media Encoder to the collection of applications running in parallel. Ogg Vorbis was set to work converting an audio file into its own OGG format, while Windows Media Encoder tackled converting a 108 MB AVI file into WMV format. Thus, the CPU had to handle four concurrent tasks in this test.

Multitasking III

This scenario seeks to simulate a typical daily set of business computing activities on the desktop: while the user runs one application, a virus scan runs in the background. In our scenario we returned to FineReader 8 and used it to convert War and Peace from PDF into MS Word DOC format, at the same time that we scanned a large installation directory for viruses. Everybody's been here, and many coworkers in large companies have been known to make a habit of disappearing for a mid-day break while such a scan is running. Ever since the IT department set up its remote virus scans, user productivity has tanked while the scans were active.

16. Application Test Results
DivX 6.1

Because the DivX 6.1 codec runs faster on multi-core systems, the Core Duo T2500 blows everything else away. Even compared to the fastest running Pentium M (780) it still shows a performance advantage of a good 25 percent.

Adobe Photoshop CS 2

The dual core system is clearly faster than a single core system from the second Centrino generation (Pentium M 760) running at the same clock speed. Compared to the faster Pentium M 780, however, it shows no speed advantage. This is presumably because only three of the seven filters in the Intel-developed test scripts were optimized for multi-threading. In other words, when compared to the Pentium M 780, the Core Duo barely pulls ahead when running only those three filters optimized for multi-threading. When the tables are turned, and both machines run only the four filters that aren't optimized, the higher core clock rate for the Pentium M 780 lets it cross the finish line first.

AVG Anti-Virus 7.1

This application is obviously not optimized for multi-core processing. Even the Pentium M 760, which runs as the same speed as the Core Duo T2500, beats the dual core processor on this test.

ABBYY FineReader Pro 8.0

This next result is puzzling. ABBYY FineReader definitely belongs to the class of applications optimized for dual core CPUs, as results from our recent Pentium D Review clearly illustrate. That said, we monitored core loads while running this application on the Core Duo T2500 with Task Manager, and were astonished to see that FineReader used one core exclusively and left the other idle.

17. Windows Media Encoder 9

Windows Media Encoder has been optimized for multi-core platforms for some time now. Thus, the dual core Centrino platform lets no grass grow beneath its feet while running this test. When compared to the Pentium M 760, the Core Duo CPU polished off this task some 65 percent faster, and even the M 780, with its faster core clock rate, still took nearly 50 percent longer to complete the file conversion task.

Autodesk 3D Studio Max 8

In this case, the Core Duo T2500 does not fare well against its older Pentium M 760 and Pentium M 780 brethren. As an examination of core loads with Task Manager shows, 3D Studio Max 8 utilizes only about seventy percent of the capacity of both cores. This suggests strongly to us that more work is required on the part of the software developers; they need to do a better job of optimizing their code for multi-core processors, as is the case with FineReader 8.0.

Pinnacle Studio 10 Plus

This is a case where the Core Duo really shines. The independent processing units not only help with rescaling and filtering of video data, but they also presumably help give a noticeable boost to the additional SSE3 functions used.

SiSoft Sandra 2005 R2

Even though both of the notebooks built around Intel technologies use the same memory modules with the same timings in dual channel mode, memory bandwidth in the Centrino Duo platform is nearly 1 GB/s greater. Because of its integrated single channel DDR memory interface, the AMD Turion 64 laptop is completely vanquished here, landing in last place.

18. Results From The Multitasking Scenarios
Multitasking I: WinRAR + Lame

The system with the dual core CPU far outperforms those with single core CPUs.

Multitasking II: WinRAR + Lame + Ogg + WMV

When running four applications in parallel, the Centrino Duo system outclasses all single core notebooks.

Multitasking III: FineReader + AVG Anti-Virus

Those who have a dual core notebook need not disappear for an extra morning coffee break when a virus scan runs! The advantage of a Core Duo notebook may appear small in this case, but these results can't dispel the fact that even when such a system is heavily loaded, it still responds promptly to keyboard input. That means you can let your virus scanner run in the background, yet still keep working on a document or continue surfing the Web.

19. Office Applications: SYSmark 2004 SE

The SYSmark 2004 SE benchmark tests concentrate exclusively on performance; battery life is irrelevant. These tests are constructed so that the notebook must be plugged into a wall socket. SYSmark 2004 SE uses real applications in its benchmark tests. In this benchmark suite, scripts run this software automatically to simulate typical application use and user behavior.

The SYSmark 2004 SE tests are divided up into two benchmark scenarios: Internet Content Creation and Office Productivity. There are three groups of tests in the Internet Content scenario, including 3D Content, 2D Content, and Web Publication. The Office Productivity also consists of three groups of tests: Communications (E-mail, Calendar, and Web browsing) plus Document Development and Data Analysis.

All values that SYSmark 2004 SE reports are based on average response time. All these values are likewise scaled by how they relate to a standard reference system configured with average components and capabilities. This reference system is granted a standard point score of 100, to provide a ready point of comparison to the system under test. That said, even though MobileMark 2005 takes the same general approach, office productivity values for MobileMark 2005 and SYSmark 2004 SE are not directly comparable.

Here, you'll find the SYSmark 2004 SE benchmark results diagrams for the Asus Centrino Duo system, as well as for the comparison systems, all of which are based upon the older, second generation Centrino platform. Our discussion and analysis follows these diagrams.

20. SYSmark 2004 SE, Continued

SYSmark 2004 SE Analysis And Conclusions

The SYSmark 2004 SE results show that the Asus A6JA Core Duo system runs significantly faster than a single core system operating at the same core clock speed. They also show a clear advantage over systems built around AMD technology. The Overall Score is about 30 percent higher than for any single core system. If you look more closely at the two component values for Office Productivity and Internet Content Creation, you'll see that values for Office Productivity are only about 11 percent higher than for single core systems, but that for Internet Content Creation the difference is a much more impressive 48 percent.

This situation is easy to explain as a natural result of the fact that so many of the applications used to make up the workload for Internet Content Creation in SYSmark 2004 SE are already optimized for dual core systems. Good examples of such software include Windows Media Encoder and Photoshop, also tested separately in this article.

In the Office arena the performance advantage narrows, because these applications work well with either single core or dual core processors, but run faster when two independent processors are available than when only one is on call. Another contributor to improved performance is higher memory bandwidth, despite working with identical memory modules and memory timings. We already reported on this phenomenon earlier in discussing SiSoft Sandra results.

21. Battery Life: MobileMark 2005

The MobileMark 2005 benchmarks test the behavior of a mobile computer running on battery power. There are four battery life tests: Office productivity, Read and search, DVD playback, and Wireless Web browsing. Every test uses real applications and runs from the moment at which the power cord is removed from the notebook until the moment when the battery runs completely out of power. Test results are written to a log file at 10 second intervals.

MobileMark 2005 also calculates two types of performance values while these tests are running: an overall performance value and the average response time for the completion of all tasks in the office productivity test. The overall performance value builds on average response time, but is stated in terms of a standard reference system outfitted with average components that's scored at 100 points for comparison purposes.

The following diagrams depict the MobileMark 2005 test results for the Asus Centrino Duo system as well as for comparison systems, all of which were built using the older, second generation Centrino platform. Our analysis and conclusions follows after these diagrams.

22. MobileMark 2005, Continued

MobileMark 2005 Battery Lifetime And Performance Measurements: Analysis And Conclusions

Most readers will look at these results and wonder if the new platform really gobbles that much juice, or if the THG crew simply goofed. However, neither is really the case; we didn't mess up, and the abysmal battery life times reported are certainly not the fault of an enormously power-hungry CPU. It's far more likely that they come from the high-performance graphics chip along with its 512 MB of dedicated video RAM. Both of these suck a lot of juice from the battery. We'll explain how we arrived at this conclusion in the final part of this section of our review. Perhaps it's the combination of the chipset and the graphics card? Maybe, but that's pure speculation. What we can prove is that the test system put at our disposal has a huge appetite for power.

The following charts clarify further how truly high the average power draw was in our test system, including its power consumption, when compared to the other two test systems in all three different MobileMark 2005 scenarios. Then too, our Centrino Duo test system consumed an average of 31 to 34 watts. This value is far too high to attribute only to the CPU, simply because it isn't even that heavily loaded when running either office productivity or DVD playback tests.

On to some good news. In terms of performance, the Core Duo system shows itself as somewhat faster than an older Centrino single core system that runs at the same core clock rate. What we can't answer is why that speed difference isn't as dramatic as in the Office Productivity tests for SYSmark 2004 SE. This question should more properly be directed at BAPco, the guardian and protector of the mix of applications and the scripts used to put them to work in these tests.

That's it for the good news. We couldn't prove that the new WLAN module is more energy efficient than the old one, but we believe that's not the case.

23. Energy Drain: Graphics Chip Or Chipset?

Next, let's take a look at the following three diagrams. The first one shows the power draw for the three test systems running in idle mode. The second illustrates what happened when we loaded the CPUs in all three notebooks as heavily as we could using the BurnMAX tool, and measured their power consumption. The final diagram shows the difference between the values read in idle mode versus those read under heavy load for all three candidates.

As you can see in the third chart, running either one of the two cores in the Core Duo T2500 processor at capacity boosts power consumption in the Centrino Duo system by about 13 Watts. When both cores are run at capacity, power consumption climbs by not quite 21 Watts. For an older Centrino system with a Pentium M, the power consumption under maximum load is also nearly 21 watts, even though a Pentium M 760 includes only one processing unit.

What can we conclude from these measurements? For one thing, the Core Duo T2500 is significantly better at conserving battery power than a Pentium M that runs at the same clock rate - at least, when only one core is heavily loaded, and the L2 cache isn't heavily used. Once you fire up both cores, the Duo starts to draw significantly more power. But even then, it's not drawing more, or perhaps only a small bit more, than a Pentium M 760.

By extension it follows logically that the abysmal results we obtained for battery life for the Centrino Duo test system while running the MobileMark 2005 benchmarks aren't caused by a power gobbling CPU. That's because its power consumption, usually stated in more approachable language as energy use, tops out at 21 Watts, which is in keeping with both our reasoning and our measurements.

So if that's true, where's the juice going? Is the graphics card consuming inordinate amounts of current? Might the logic that shuts down unused PCI Express lanes when used with dedicated GPUs be falling down on the job? This is a known problem that has already been observed in Sonoma systems, and discussed and documented with the developers, though never really said aloud in public nor officially acknowledged. Could it be that a substantial chunk of battery power is converted to heat in the brand-new ICH7-M chipset?

Many things are possible, but if we're willing to believe our well-informed sources, a problem with the USB 2.0 controller may be at fault. We can neither predict nor yet prove if this behavior will also apply to production notebooks in this series - remember, ours was a prototype. But we are convinced that Intel and other parties involved will be highly motivated to find and fix this problem as quickly as they can. It could even be the early stepping model of the chipset (NB Rev 03, SB Rev 02) that Asus built into our test machine.

24. Summary And Conclusions

Yonah shows that Intel's engineers have achieved something that those who build automobile engines can only dream about: putting two engines in one device, resulting in better performance without excessive fuel consumption. That said, creating an eight-cylinder engine out of two four-cylinder motors actually creates a pretty powerful engine - a bit of trickery, but usually practiced in the car business. Still consumption for a V8 engine in moderate, everyday use is around 20 to 30 percent higher, when compared to a four cylinder engine.

The situation for Intel's Yonah - whose birthplace is in Haifa, Israel, as for so many other good CPUs of recent vintage - is different. There, the developers have succeeded in artfully improving performance by a wide margin, without sending power consumptions sky high.

Nevertheless we must ask ourselves where the bulk of battery energy goes missing. Our test system with its dedicated graphics chip ran out of juice in just a bit over two hours when running on battery.

We can't blame the CPU as we've already shown. Yonah by itself, perhaps better identified as the Core Duo processor, is definitely one of the most efficient and energy saving (mobile) processors we've ever seen. Whether battery power is disappearing into the ATI graphics chip or the chipset itself is something we can't say with certainty.

Then too, there are rumors that earlier versions of the ICH7M had problems with the USB 2.0 controller that caused excessive consumption of battery power. As the old saying goes, "there's some germ of truth in every rumor." For our part, we intend to dig into a dual core system with an integrated graphics core and a 945GM chipset to help us determine where that excess power is going.

Whether or not the new platform proves that Intel's new motto "Leap Ahead" is a real step forward, is only of marginal interest in this situation. One thing's for sure: Yonah, as implemented in the dual core technology in the Centrino Duo platform, is genuinely exciting stuff. By itself, it offers a great reason to wish the developers congratulations for a job well done. Better yet, this new platform costs no more than the old one - at least, not for the next twelve months. As long as Windows remains mostly 32-bit, so will Yonah.

In applications created to exploit the capabilities of dual core processors, single task use experiences a verifiable jump of up to 65 percent (Windows Media Encoder). Individual video editing applications such as Pinnacle Studio 10 Plus also benefit substantially from dual core notebook technology as well, showing a speed boost of 65 percent. Even those applications that aren't optimized can benefit from the new processor. Its faster front side bus, plus the added power of two independent processors and an improved memory interface in the memory controller hub, all help speed things up. In our own carefully crafted multitasking scenarios, the new platform led the pack across the board, with a lead of 30 to 50 percent ahead of a Pentium M Centrino system running at the same core clock speed. The results from off the shelf benchmarks such as SYSmark 2004 SE also validate our observations.

25. Summary And Conclusions, Continued

Naturally, Intel's new mobile platform can't address every conceivable performance problem. Most everyday home and office applications won't run appreciably faster, and some may even run a bit slower. Removing such obstacles is the job of the software developer, not the processor vendor, especially when it comes to cleaning up legacy issues that have been preserved too long in program code.

Another bottleneck that continues to hinder a genuine desktop experience on notebook computers is the relatively lame hard disks built into mobile computers these days. Higher rotational speeds are not the final solution, but they would certainly help. Classic RAID arrays consume too much power and are relatively expensive - too much for most notebook vendors to consider installing them in their products. At this point, the best one can do is put faith in the power of human ingenuity and innovation at the few remaining hard disk vendors, hoping that they come through with some kind of miracle, however minor that might turn out to be.

Despite these various disclaimers, one shouldn't underestimate the "Ah!" effect that can occur when using a dual core notebook. You could be working on some application and realize that a virus scan is running in the background while you switch around between a number of other applications, while the system remains ready to respond to the keyboard without a noticeable delay.

Gamers, who look for notebooks with dedicated high-end graphics chips to let them indulge their passions, should wait for dual core technology notebooks in any case. That's because 3D games (such as Call of Duty, Quake 4, or King Kong), which normally overwhelm even fast graphics processors and high-performance single core CPUs, run flicker-free on the new dual core processors.

Those who simply must go out and buy a new notebook in the next few weeks shouldn't lose too much sleep either. Battery lifetimes of a Core Duo or Core Solo system won't differ significantly, that is for sure. As we're discovering, this is the only, if pretty significant, criticism we can level at these new platforms.

A little head-banging may, however, ensue when dealing with the lack of availability of these new systems. The many announcements from Core Duo system vendors would seem to suggest that these systems should show up on store shelves soon. But experience teaches us that it will probably be another couple of weeks before the notebook you want so badly ends up in your hot little hands - and inside information confirms it. By then, we also hope to determine where the large amounts of battery power our test system consumed actually went.

One real step forward - in the sense of Intel's "Leap Ahead" slogan - would be something else entirely, at least in our opinion. That is, we'd like to see Intel work in collaboration with component and subsystem vendors to finally deliver a system architecture that makes an affordable notebook available to the teeming masses of ordinary notebook users who want an average battery life of five to six hours. But please, not by requiring use of five pound supplemental batteries, either...

Finally, we'd like to share the following tip. Bargain hunters (not trend-setters) should look for deals on what now becomes an "older" generation of Centrino (Sonoma) systems. Even the "good old" Pentium M (Dothan) is still a good, relatively energy efficient mobile CPU that can satisfy business computing needs quite nicely.

Whoops! We nearly forgot AMD. Can we dare to hope that we'll soon hear news from Texas that might really represent a step forward? This will probably mean something like a DDR2 memory interface for the next Turion 64 generation. But there's no immediate cause for alarm: Surely something new will come from the folks at AMD; of that, we're completely convinced.

How about something like a mobile 64-bit dual core mobile processor that consumes less power than Intel's brand-new dual core 32-bit offering? This would pair up especially well with Microsoft's new Vista operating systems and Office suite, because both should include massive 64-bit enhancements. And who wants to be stuck with a notebook twelve months from now that can't handle 64-bit programs?