Don’t you hate it when you’re on a plane, three-quarters of the way through your favorite movie, when the notebook you’re watching on runs out of juice? It takes a miserly mobile platform to last an entire feature film and continue computing on after it’s over, and those are fairly few and far between.
The first Arrandale-based notebook to land in our lab is armed with a full complement of media-oriented functionality, but I'll spoil the suspense and come right out with the fact that it can’t quite finish a Blu-ray movie.
That’s not to say the Asus K42F isn’t a winner when it comes to longevity. We made it 120 minutes through Transformers on Blu-ray before the unit’s 63Wh battery gave out. More impressive, the K42F played back 300 in its entirely (on DVD) and still had 44% of its battery left.
In comparison, back in October, we gave you a look at Intel’s Mobile Core i7-920XM—the first Nehalem-based processor to tackle the desktop replacement notebook market, not counting the Bloomfield-based behemoths we've seen. With a 55W TDP, though, and paired up to a discrete graphics adapter, we were actually somewhat disappointed with the system’s power consumption, even if it did deliver superior performance versus previous-generation Montevina-based machines. That machine only made it through the first 44 minutes of 300.
But Intel’s Clarksfield-based processor was never meant to be the shining star in the company’s Calpella mobile platform. And ever since our desktop replacement preview, we’ve been anxiously awaiting Arrandale, the processor that’d power notebooks for the rest of us: from medium-sized designs to thin-and-lights and ultra-portables. Finishing our DVD movie with almost half of its battery left was quite a feat for Asus' first Arrandale offering. What else can the little 14" notebook do well?
A Platform Built To Dominate
Of course, Arrandale is the mobile equivalent of Clarkdale, which we detail in Intel Core i5-661: Clarkdale Rings The Death Knell Of Core 2. It leverages the same 32nm high-k / metal gate manufacturing process, which helps pull down the power consumption of these new chips to 35W, 25W, and 18W, depending on the model you choose.
“But wait,” you say. “Isn’t that the same as most of Intel’s 45nm Core 2 Duo standard-voltage and medium-voltage chips? Where’s the improvement?”
That's the BGA version of Arrandale with its SFF platform controller hub
Like Clarkdale, Arrandale includes two die on a single package—the 32nm silicon consists of the dual-core, Hyper-Threading-equipped processor, while the 45nm die includes graphics, memory control, and PCI Express. Integrating all of that functionality into the CPU negates the need for a traditional northbridge. So, again, we’re presented with a two-chip platform, akin to Lynnfield/P55 and Clarkdale/H55/H57. Axing the middle chip—the GM45 graphics and memory controller hub, in the Montevina platform—eliminates a component that uses up to 12W. So, while Arrandale itself doesn’t represent a huge power savings, the platform it enables has the potential to both outperform and outlast any comparably-equipped notebook today.
Complementing the new processors is a host of chipsets and Centrino-branded wireless modules. Moreover, we have one of the first examples of Arrandale in action here in our lab. Today we’ll be taking Asus’ new K42F notebook for a spin and comparing it against an HP notebook configured as similarly as possible.
If you’ve already read my Clarkdale coverage, then you know the nuts and bolts of Arrandale. It’s the same dual-die package with a 32nm CPU and 45nm graphics/memory/PCIe controller. The main differences between Arrandale and Clarkdale are: frequencies (of the CPU and GPU), DDR3 memory support, power consumption, packaging, and pricing.
Alright—perhaps there are a few things to talk about here.
There are a total of 11 new mobile processors being launched (as opposed to just six desktop chips). Five are Core i7-600-series CPUs, four are Core i5s, and two are Core i3s. If you’ve read my mini-rant about Intel’s naming in the Clarkdale piece, the same applies in this piece—you’ll truly need a reference chart in order to make any sense of how model names relate to specifications.
The new Core i7s are dual-core chips with Hyper-Threading enabled, sporting 4MB of shared L3 cache, and available in power profiles ranging from 18W to 35W. Forget what you thought determined a Core i7 on the desktop—that’s out the window here, as you'll find Mobile Core i5 and Core i3 processors that run faster than the entry-level Core i7s. Why is this? Only the Core i7-620M is a standard voltage 35W part. The i7-640LM and i7-620LM are medium-voltage components with 25W TDPs. Intel’s i7-640UM and i7-620UM feature 18W TDPs, dropping dual-channel DDR3 memory support from 1,066 MT/s to 800 MT/s. And although their names all differ by just a single letter or number, the five i7s run at base clock rates of 1.06-2.66 GHz and Turbo up to 2.13 GHz to 3.33 GHz.
| Intel Mobile Core i3/5/7 Lineup For 2010 | ||||||||
|---|---|---|---|---|---|---|---|---|
| Base Clock | Max. Turbo Clock | Cores / Threads | DDR3 Memory | TDP | Package | Pricing | Base Graphics Freq. | |
| Core i7-920XM | 2 GHz | 3.2 GHz | 4/8 | 1,333 MT/s | 55W | rPGA BGA | $1,054 | - |
| Core i7-820QM | 1.73 GHz | 3.06 GHz | 4/8 | 1,333 MT/s | 45W | rPGA BGA | $546 | - |
| Core i7-720QM | 1.6 GHz | 2.8 GHz | 4/8 | 1,333 MT/s | 45W | rPGA BGA | $364 | - |
| Core i7-620M | 2.66 GHz | 3.33 GHz | 2/4 | 1,066 MT/s | 35W | rPGA BGA | $332 | 533 MHz |
| Core i7-640LM | 2.13 GHz | 2.93 GHz | 2/4 | 1,066 MT/s | 25W | BGA | $332 | 266 MHz |
| Core i7-620LM | 2 GHz | 2.8 GHz | 2/4 | 1,066 MT/s | 25W | BGA | $300 | 266 MHz |
| Core i7-640UM | 1.2 GHz | 2.26 GHz | 2/4 | 800 MT/s | 18W | BGA | $305 | 166 MHz |
| Core i7-620UM | 1.06 GHz | 2.13 GHz | 2/4 | 800 MT/s | 18W | BGA | $278 | 166 MHz |
| Core i5-540M | 2.53 GHz | 3.06 GHz | 2/4 | 1,066 MT/s | 35W | rPGA BGA | $257 | 533 MHz |
| Core i5-520M | 2.4 GHz | 2.93 GHz | 2/4 | 1,066 MT/s | 35W | rPGA BGA | $225 | 533 MHz |
| Core i5-520UM | 1.06 GHz | 1.86 GHz | 2/4 | 800 MT/s | 18W | BGA | $241 | 166 MHz |
| Core i5-430M | 2.26 GHz | 2.53 GHz | 2/4 | 1,066 MT/s | 35W | rPGA BGA | - | 533 MHz |
| Core i3-350M | 2.26 GHz | - | 2/4 | 1,066 MT/s | 35W | rPGA BGA | - | 533 MHz |
| Core i3-330M | 2.13 GHz | - | 2/4 | 1,066 MT/s | 35W | rPGA BGA | - | 533 MHz |
The four Core i5s hardly fare better. They, too, are dual-core models with Hyper-Threading enabled. But instead of 4MB shared L3 cache, they’re armed with 3MB. Three models are 35W TDP parts, but they span the i5-500M- and i5-400M-series. Why the drop to -400? The only explanation we can see is a less-aggressive Turbo Boost implementation on the entry-level model, highlighted in the chart above. There’s a single 18W low-voltage part in the Core i5 lineup, which drops to DDR3-800 memory support and a 1.06 GHz base clock rate. With thermal headroom to spare, though, the chip can Turbo up to 1.86 GHz.
The two Core i3s are, again, dual-core, Hyper-Threading-equipped CPUs with 3MB shared L3 cache and DDR3-1066-compatible. They’re both 35W chips, which makes sense because neither supports Turbo Boost, so Intel isn’t able to set a low base clock and rely on Turbo to bring performance up when thermal headroom allows.
Core 2 Duo P8700...
...Core i5-540M
Pricing across the lineup is aggressive, ranging from $225 to $332 (three of the lowest-end models aren’t being listed at launch).
I went into ample depth on the HD Graphics built into Intel’s Clarkdale and Arrandale processors—for a quick recap, pull up this page.
With that said, while the 3D hardware remains the same between desktop and mobile CPUs, the Arrandale processors more intelligently handle the interaction between power and performance. You already know Turbo Boost technology, which capitalizes on thermal and power headroom to increase clock rate.
Dynamic frequency in action...
Intel’s mobile chips get a form of Turbo Boost that the company calls dynamic frequency, which ramps up the GPU’s core clock in response to graphics-intensive workloads. The entire processor package (consisting of 32nm CPU and 45nm GPU/memory/PCIe) is still subject to a maximum TDP rating. However, the two components are able to balance that budget depending on perceived utilization.
For example, in the dual-core standard voltage (35W) SKUs, the 32nm CPU die is actually rated for up to 25W typical consumption, while the integrated graphics and memory controller uses up to 12.5W with total package power not to exceed 35W. Within that power budget, the fastest CPU core (Intel’s Core i7-620M) runs at a 2.66 GHz base clock rate and can Turbo up to 3.33 GHz with a single core active. Or, if there’s a demanding workload hammering the GPU, available TDP can take the graphics core from 500 MHz as high as 766 MHz. In extreme cases, which Intel defines as occasions when the package isn’t thermally-constrained and able to violate its maximum power limits, the processor may use up to 29W, leaving 6W to the graphics and memory controller. Or, the graphics may use up to 20W, leaving 15W to the CPU.
The medium-voltage 25W chips are kept on an even tighter leash, scaling CPU speed from up to 2.13 GHz to as much as 2.93 GHz via Turbo Boost or pushing graphics from 266 MHz up to 566 MHz. Typically, the CPU will use up to 18W and the graphics core 9.5W. But again, there are concessions made for extreme cases in which you’ll see a 21/4W or 12/13W split between the two components. The point is that there’s enough intelligence built into these processors to manage a peak power ceiling given two die on the same package doing different jobs.
All in all, the dynamic frequency capability is really quite cool. And while its absence will be lamented by some on the desktop Clarkdale processors, Intel is already running the graphics core at 900 MHz on its Core i5-661 and 733/533 MHz on its other launch SKUs.
Switchable Graphics
Mentioned previously in our Clarksfield (Core i7-920XM) coverage, switchable graphics is now supported across the Arrandale-based processors and 5-series chipsets. Of course, switchable graphics is the ability to swap between the CPU’s integrated graphics core and a discrete GPU without rebooting.
In that first exploration into Calpella, we decided that switchable graphics made the most sense matched to these Arrandale CPUs, since they already include integrated graphics as a standard capability. Moreover, there will undoubtedly be notebook vendors who pair mainstream processors with discrete GPUs for mid-range gaming capabilities. So, while switchable graphics has seen relatively little traction thus far (despite technically being supported since the days of Montevina), now is the time, if ever, we’d see it become more popular.
Along with its 11 new mobile processors, Intel is also launching a quartet of platform controller hubs. From lowest to highest, in order of pricing: HM55, HM57, QM57, QS57. Add in the PM55 already being used to support Clarksfield processors and you have a total of five mobile chipsets from which to choose in the current-generation Calpella platform.
Given the degree of integration on the processor side (leaving relatively little for core logic to handle), the differences between these five SKUs are fairly subtle, so let’s start with yet another chart and break them down from there.
| QM57 | QS57 | HM57 | PM55 | HM55 | ||
|---|---|---|---|---|---|---|
| Firmware Package | 8MB | 8MB | 8MB | 4MB | 2MB | 4MB |
| AMT 6.0 | Yes | Yes | - | - | - | - |
| Remote PC Assist For Consumer | - | - | Yes | - | - | - |
| Identity Protection | - | - | Yes | - | - | - |
| Rapid Storage 9.5 | Yes | Yes | Yes | Yes | Yes | Yes (AHCI-only) |
| Anti-Theft | Yes | Yes | Yes | Yes | - | Yes |
| FIS-Based Port Multiplier Support | - | - | - | - | - | - |
| USB 2.0 | 14 | 14 | 14 | 14 | 14 | 12 |
| 2.5 GT/s PCI Express | 8 | 8 | 8 | 8 | 8 | 6 |
| SATA 3 Gb/s | 6 | 6 | 6 | 6 | 6 | 4 |
| Legacy PCI | 4 | 4 | 4 | 4 | 4 | 4 |
| Integrated Graphics w/ PAVP 1.5 | Yes | Yes | Yes | Yes | - | Yes |
Right off the bat, we see that the QM- and QS- models are intended more for businesses than consumers. AMT 6.0 with Remote PC Assist is used by IT administrators and VARs to remotely manage and secure hardware assets—a great feature if you’re the one responsible for keeping tabs on pricey notebooks, especially in larger organizations where inventorying equipment is particularly difficult.
HM57 and HM55 (like H57 and H55 on the desktop) are more relevant to the broader market of consumers.
HM55 includes 12 USB 2.0 ports, six 2.5 GT/s PCI Express links, four SATA 3 Gb/s ports, support for four PCI devices, Anti-Theft technology, and the AHCI component of Intel’s Rapid Storage technology suite (not the software-based RAID support). Of course, Intel also adds its management engine, enabling the protected audio/video path needed for Blu-ray video playback and high-def audio bitstreaming via integrated graphics.
HM57 is available in two different forms. Both step up with 14 USB 2.0 ports, eight PCI Express links, six SATA ports, up to four PCI-based peripherals, and the same protected audio/video path. The “lower-end” version employs up to a 4MB firmware package, while the “higher-end” implementation uses as much as 8MB of space. The larger firmware makes room for Identity Protection technology and Remote PC Assist technology for the consumer space—a version of what Intel enables on the QM57 and QS57—allowing befuddled home users to hit a button, key in a code, and get remote support from a remote tech offering service.
As you’ve no doubt already realized, all four of these platforms are very similar from an I/O standpoint, and differentiated by turning switches on various value-adds on and off. Fair enough—that’s the way it’s destined to be anyway as an increasing amount of technology is integrated into the processor itself.
The first notebook to breeze through our lab based on the Calpella platform was Eurocom’s Cougar, which employed the Mobile Core i7-920XM. At the time, Clarksfield was the only processor design available for Calpella. It’s hardly a surprise, then, that the previous-generation Montevina collection of 4-series chipsets, Core 2 CPUs, and WiFi Link wireless networking controllers is still most prevalent when you go shopping for notebooks. Expect that to change now that Intel is adding its 5-series chipsets, Arrandale-based Mobile Core i5 and Mobile Core i3 processors, and Centrino-branded wireless modules.
As part of our launch coverage, we have the first Calpella notebook with all of these new components: Asus’ K42F. The pre-production configuration we received isn’t exactly representative of what you’ll find at e-tail though, so let’s go through what is and what isn’t included with this promising-looking notebook.
Asus is purportedly planning to launch a range of these SKUs with a number of different Core i3, Core i5, and Core i7 processor options in Q1. This one, slated to cost $999, is spec’ed out for a Core i5-520M CPU, 4GB of DDR3 memory, a 320GB 5,400 RPM mechanical hard drive, a BD-ROM drive, 802.11n wireless, and an eight-cell battery. You’ll get Windows 7 Home Premium bundled, too.
Our sample shipped with a Core i5-540M, which is really an almost-negligible step up that maintains a 35W TDP, but pushes the CPU’s base frequency to 2.53 GHz and its maximum Turbo’ed clock to 3.06 GHz. You’ll see why this is a welcome upgrade when it comes time to stack this notebook up against a competing Montevina machine.
We also received our sample with a 500GB 5,400 RPM hard drive—slightly larger than the stock 320GB disk. This didn’t really matter in our testing, though, because we substituted in our own second-generation Intel 160GB SSD to alleviate storage bottlenecks. The 500GB drive was useful for conducting MobileMark 2007 testing on clean copies of Windows 7, but that’s really the only time we went with mechanical storage.
The only other change, Windows 7 Ultimate (versus Windows 7 Home Premium) is simply what we’ve standardized as our testing OS in the lab, and has no real effect on performance.
Up Close And Personal
So let’s take a look at the Calpella-based notebook enabled by Intel’s Arrandale processor and 5-series chipset.
It’s significantly smaller than Eurocom’s Cougar mobile workstation, with its 14” 1366x768 display, naturally. Nevertheless, a full-sized keyboard ensures you that this isn’t some flimsy sub-compact. We’ll withhold judgment on the chassis itself, given its pre-production status. However, one aspect that likely won’t be changed between now and production is the extremely pressure-sensitive DVD multi-recorder drive, which had a habit of popping out at the slightest nudge.
With that said, the K42F is lined with a number of useful ports and connectors. The left side of the notebook sports a pair of USB 2.0 ports, HDMI output, VGA output, and a 1/8” jack for connecting headphones.The HDMI is a nice tough for those who want to use their notebook in a home theater environment.
There’s a media card reader dead-center under the notebook’s front lip, but otherwise nothing else aside from a pair of vents.
The system’s right side hosts its optical drive (in our case, a multi-function BD-ROM, included with the standard configuration from Asus), another USB 2.0 port, gigabit Ethernet, and the DC power input.
Because the notebook is technically what most folks would consider a thin-and-light, it’s designed for compactness. Most of its back side is populated by battery and swivel; there aren’t any connectors back there.
| Test Laptops | ||
|---|---|---|
| Model | Asus K42F | HP Pavillion dv4-1555dx |
| Processor | Intel Core i5-540M (Arrandale) 2.53 GHz, PGA988, 3MB Shared L3, Hyper-Threading, Power-savings enabled | Intel Core 2 Duo P8700 (Penryn) 2.53 GHz, PGA478, 3MB Shared L2, Power-savings enabled |
| Graphics | Integrated Intel HD Graphics | Integrated GMA 4500MHD Graphics |
| Memory | 4GB DDR-1333 | 4GB DDR3-1066 @ 7-7-7 |
| Hard Drive | Intel SSDSA2M160G2GC 160GB SATA 3 Gb/s | Intel SSDSA2M160G2GC 160GB SATA 3 Gb/s |
| Software And Drivers | ||
| Operating System | Windows 7 Ultimate 64-bit | Windows 7 Ultimate 64-bit |
| Platform Driver | 9.1.1.1020 | 9.1.1.1025 |
| Graphics Driver | 15.16.4.64.2008 | 15.16.2.64.1986 |
Benchmarks and Settings | |
|---|---|
Audio Encoding | |
iTunes | Version: 9.0.2.25 (64-bit), Audio CD ("Terminator II" SE), 53 min., Default format AAC |
Video Encoding | |
TMPEG 4.7 | Version: 4.7.3.292, Import File: "Terminator II" SE DVD (5 Minutes), Resolution: 720x576 (PAL) 16:9 |
DivX 6.8.5 | Encoding mode: Insane Quality, Enhanced Multi-Threading, Enabled using SSE4, Quarter-pixel search |
XviD 1.2.2 | Display encoding status=off |
MainConcept Reference 1.6.1 | MPEG2 to MPEG2 (H.264), MainConcept H.264/AVC Codec, 28 sec HDTV 1920x1080 (MPEG2), Audio: MPEG2 (44.1 KHz, 2 Channel, 16-Bit, 224 Kb/s), Mode: PAL (25 FPS), Profile: Tom’s Hardware Settings for Qct-Core |
| HandBrake 0.9.4 | Version 0.9.4, convert first .vob file from The Last Samurai to .mp4, High Profile |
Applications | |
Autodesk 3ds Max 2010 (64-bit) | Version: 2009 Service Pack 1, Rendering Dragon Image at 1920x1080 (HDTV) |
WinRAR 3.90 | Version 3.90 (64-bit), Benchmark: THG-Workload (334 MB) |
7zip | Version 4.65, Built-in Benchmark |
| Adobe Photoshop CS4 | Radial Blur, Shape Blur, Median, Polar Coordinates filters |
| AVG Anti-Virus 9 | Virus scan of 334MB of compressed files |
Synthetic Benchmarks and Settings | |
3DMark Vantage | Version: 1.02, GPU and CPU scores |
PCMark Vantage | Version: 1.00, System, Memories, TV and Movies, and Productivity benchmarks, Windows Media Player 10.00.00.3646 |
SiSoftware Sandra 2010 | CPU Test=CPU Arithmetic/MultiMedia, Memory Test=Bandwidth Benchmark |
| Games | |
| World of Warcraft | Low Quality Settings, No AA / No AF, vsync off, 1024x768, Patch 3.3, Dalaran circuit, FRAPS |




As we start in with our synthetics, the differences between these two mobile platforms is immediately apparent. The PCMark Vantage Overall suite score quite obviously favors Intel’s Arrandale processor. The Memories, TV and Movies, and Productivity suite scores follow suit, though not quite to the same degree.



We already know that there’s often little correlation between synthetic measurements of arithmetic/multimedia performance and real-world metrics. But Sandra 2010 nevertheless demonstrates a notable advantage in favor of Intel’s Arrandale-based Core i5-540M.
Most interesting is the memory bandwidth, which tells us that the on-package memory controller is enabling significantly more throughput than GM45’s memory controller. Of course, this is less bandwidth than you’d get from the Mobile Core i7-920XM, which includes an on-die (versus on-package) memory controller.



In our desktop Clarkdale coverage, we compared 3DMark performance using the Performance preset, if only to keep the results relevant to the discrete platforms used to prevent a graphics bottleneck. Here, though, we step back to the Entry preset in the interest of generating more meaningful numbers. Given the Overall and GPU results, it’s clear that HD Graphics are more effective than the GM45’s GMA 4500MHD controller.
The biggest performance boost comes from the 32nm host processor, which almost doubles the performance of Intel’s Penryn-based Core 2 Duo P8700 in the physics- and AI-oriented processor tests.

We’re not going to spend a ton of time talking about gaming. After all, you’re going to be fairly limited in the number of titles that will run well on an integrated graphics core—even if it has been pulled into the CPU package.
But a quick jaunt around Dalaran in World of Warcraft shows us that frame rates do exceed anything that was possible on a Montevina-based notebook. With that said, dropping detail settings to Low and the resolution to 1024x768 is not a recipe for pretty visuals. When it comes to mobile computing, you’ll have to make a critical decision. Sacrifice battery life and invest in discrete graphics or settle for an integrated GPU and give up 3D gaming.

It isn’t hard to imagine using a notebook for converting your favorite CDs to iTunes-compatible .aac files. The Core i5-540M benefits from Turbo Boost technology in this single-threaded title, shaving 10 seconds off of the task.

Solid utilization of Hyper-Threading and an on-package memory controller gives the Mobile Core i5 a notable lead versus Intel's Core 2 Duo architecture in MainConcept. When you consider the fairly similar platform power consumption figures between these two machines, such a performance advantage is fairly incredible.

The same optimizations that make MainConcept a quicker application to run on Arrandale-based systems also affect the freely-available HandBrake title. Here, we see our The Last Samurai transcode drop from 20 minutes to roughly 13 minutes by virtue of the architectural changes made to Intel's latest-generation mobile platform.

Hyper-Threading helps accelerate our DivX transcode, but a less aggressive form of Turbo Boost technology doesn't really help the speed of our unoptimized Xvid batch job.

Our threaded Photoshop benchmark demonstrates an advantage in favor of Intel's Hyper-Threading technology, as Asus' K42F beats out the competing HP Penryn-based machine.

The difference between a dual-core processor and a dual-core processor with Hyper-Threading is staggering in AVG 9. We’ve seen this same behavior in past performance evaluations, where the anti-virus suite uses very little resources, but rewards the shift to more logical cores with a halved completion time.

We know that this one is threaded, so the massive speed-up in going with the Arrandale platform is attributable mostly to Hyper-Threading (though we also know a Turbo-equipped CPU under its TDP will still add a 133 MHz bin of acceleration, even when both cores are being utilized).

Considering that WinRAR is threaded, it’s interesting to see Hyper-Threading having little effect on this test’s overall standing. For the most part, both of these mobile platforms are even.

In a big contrast to WinRAR, 7-Zip shows a massive gain in favor of Hyper-Threading. The speed (KB/s) and rating (MIPS) components of our compression routine really accelerate Intel's Arrandale processor.

The Core i5-540M is a 35W processor, whereas Intel’s Core 2 Duo P8700 is a 25W part. Thus, it’s hardly a surprise to see the Montevina platform using less power in Prime95 than the newer Calpella design (note that these numbers were taken with no battery installed).
In fact, we certainly expected Arrandale to use more power under load based on our previous experiences with Core i7-920XM. In that story, we saw Turbo Boost and Hyper-Threading maximizing performance, depending on workload, at the expense of power consumption, whereas Core 2 Quad (or Duo, in this case) is unable to deliver a dynamic performance story.
The match-up gets much closer at idle. Although the i5-540M sports a higher TDP and two-die package, it also employs a two-chip platform and power gating to minimize the consumption of unused resources.
However, these min./max. figures don’t tell the whole story, so we also recorded a PCMark Vantage run on each notebook and charted out power use at two second intervals.
Although the 35W Core i5-540M clearly uses more power under load, it also dips well under the Core 2 Duo P8700 during Vantage’s down-time, despite the load/idle numbers above.
When you even out all of the peaks and valleys, you get 32.9W average power consumption for the Arrandale processor and 31.7W for the Penryn-based Core 2 Duo. When we factor in the fact that the Core i5-540M system finished the test 2:26 faster than the Core 2 Duo, dropping back to idle as the other machine completed its workload, we’re able to conclude that there’s finally evidence of Nehalem-based processors outdoing Core 2 when it comes to overall power consumption. The performance story tells itself. Arrandale is clearly the quicker chip, too.
This is something we’ve been waiting on for a while now. First, we heard about power gating, which would shut down unused processing cores almost completely. Then there was the inclusion of PCI Express and memory control with Lynnfield. Adding Windows 7 to the mix was supposed to optimize power usage further. But each step along the way, we saw the Nehalem design using more power than we had expected. “Wait for Arrandale, wait for Arrandale, wait for Arrandale,” was what we kept hearing. Now that Arrandale is upon us, we see the wait was worthwhile. The two-chip platform architecture, heavy integration, and shift to 32nm manufacturing means it’s now possible to get significantly better performance from a dual-core, four-thread CPU at lower overall power use than a comparably-equipped dual-core notebook based on Core 2.
In addition to our usual suite of performance and power testing, we also ran the Asus K42F and HP’s Pavillion dv4-1555dx through MobileMark 2007’s Productivity suite. Having switched out our 160GB Intel SSD in favor of a clean 500GB Seagate Momentus 5400.6 with the picky BAPCo app installed, we saw the following battery life rating and performance qualification scores:
| Battery Life Rating | Performance Qualification | |
|---|---|---|
| Arrandale (Asus K42F) | 285 minutes | 234 |
| Penryn (HP dv4-1555dx) | 235 minutes | 209 |
Clearly, the Asus wins in both performance and longevity, but let’s also take into account differences in battery capacity between these two mobile platforms. Asus outfits its offering with a 63Wh Li-Ion battery pack (14.4V, 4.4Ah), while HP employs a 47Wh power supply (10.8V, 4.2Ah).
With a significant advantage in energy storage, it’s really no wonder Asus was able to walk away with this one. Let’s normalize the results a bit to see whether the win stands up, all things equal.
| Minutes | Watt-Hours | Minutes/Wh | |
|---|---|---|---|
| Arrandale (Asus K42F) | 285 | 63 | 4.5 min/Wh |
| Penryn (HP dv4-1555dx) | 235 | 47 | 5 min/Wh |
When you do the math, the Montevina-based HP system actually lasts longer per available Wh of energy available to it, but because HP ships such a small battery, the notebook doesn’t end up lasting as long. Thus, while the previous page really demonstrated how far Intel has come in bringing down idle power consumption, distilling down the numbers reminds us that there’s a price to be paid for performance. There’s a fair chance that, if we were to turn off Turbo Boost and re-run MobileMark or re-chart a PCMark Vantage run, we’d see lower peak power use and the same low idle consumption. Unfortunately, Asus’ EFI setup doesn’t provide access to such an option, so it’ll have to remain conjecture for now.
It’s now January 2010, more than a year since we first saw Intel’s Nehalem micro-architecture emerge as Bloomfield on the desktop. While the company showed us its first Nehalem-based mobile design in Clarksfield late last year, that processor was never meant to serve as a high-volume product family—our power testing helped show why.
Fifteen months later, we have the first real Nehalem-based CPU built for a broader range of mainstream notebooks. Only now, because Intel has made the shift from 45nm to 32nm manufacturing, these Mobile Core i7, Core i5, and Core i3 CPUs actually belong to the Westmere generation.
Massive integration, including a graphics core, memory controller, and PCI Express controller in a separate 45nm die on the processor package, means the rest of Intel’s platform gets significantly simpler. Gone is the northbridge with which we’re all familiar, replaced by a very southbridge-like platform controller hub. Everything else is built into the CPU.
As a result, the consumption of these Arrandale processors is on-par with Intel’s previous mobile offerings. However, the whole platform should actually be more power-friendly than anything we’ve ever seen before from the company.
In reality, a bias toward performance via Hyper-Threading, Turbo Boost, and a dynamic graphics clock keeps these CPUs closer to their TDPs, so you actually get less battery life per available watt-hour of energy. We’re nevertheless still comfortable, based on our average power measurements and PCMark Vantage chart, saying that Arrandale boasts the best balance between desktop-class speed and true mobile usability we’ve ever seen.
Of course, realizing that balance means utilizing Arrandale’s 32nm Hillel CPU and 45nm Ironlake graphics core, so you’ll give up discrete graphics if you’re really serious about mobility (and in the process give up the ability to do much in 3D at all, despite the core’s increased complexity and DirectX 10 compatibility). Fortunately, it remains a solid engine for video playback, accelerating all three of the Blu-ray standard’s codecs, supporting multi-channel LPCM audio output over HDMI, and facilitating bitstreaming of Dolby TrueHD / DTS-HD MA should you use your notebook for playback in a home theater.
While we might not have been bowled over by Clarkdale on the desktop (especially in light of compelling competition at the $200 price point of Intel’s Core i5-661 sample), Arrandale is significantly more attractive. So long, Core 2 Duo. The wheels of progress keep on spinning, and Arrandale is playing you out.









