With Core 2 Quad and Core 2 Duo, you had a general idea of what you were dealing with upfront. Adding a Q8000- or E7000-series designator wasn’t particularly descriptive, but at least there was one tangible identifier in there for the layman to digest.
When Intel introduced Core i7 last year, the fact that there was only one Nehalem-based desktop family made it easy to say “Core i7—yeah, high-end stuff,” regardless of whether you were actually talking about the $300 i7-920 or the $1,000 i7-965.
Core i7, Core i5, and Core 2 Quad
Now you have Core i5 and another strain of Core i7; at this point the nomenclature is just jargon for everyone except for the power users who live and breathe this stuff. Let’s break it down in a neat little table, though.
| Core i7 (LGA 1366) | Core i7 (LGA 1156) | Core i5 | Core 2 Quad | |
|---|---|---|---|---|
| Processor Interface | LGA 1366 | LGA 1156 | LGA 1156 | LGA 775 |
| Number of Cores | 4 | 4 | 4 | 4 |
| Turbo Boost | Yes | Yes | Yes | No |
| Hyper-Threading | Yes | Yes | No | No |
| L1 Cache | 32KB/32KB per core | 32KB/32KB per core | 32KB/32KB per core | 32KB/32KB per core |
| L2 Cache | 256KB per core | 256KB per core | 256KB per core | Up to 12MB shared |
| L3 Cache | 8MB shared | 8MB shared | 8MB shared | No |
| Memory Channels | 3 | 2 | 2 | 2 |
| Max. Memory Rate | DDR3-1066 | DDR3-1333 | DDR3-1333 | DDR3-1600 |
| Chipset | X58 | P55 | P55 | X48 |
| Price | $284-$999 | $285-$555 | $199 | $163-$316 |
As you can see, Core i7 for LGA 1366 remains the enthusiast-class offering, sporting the most PCI Express 2.0 connectivity via Intel’s X58 Express chipset, up to three available channels of DDR3 memory support, Intel’s first generation of Turbo Boost, and Hyper-Threading.
Core i7 for LGA 1156 integrates the PCI Express connectivity (albeit 16 lanes instead of 36), sheds one memory channel, incorporates an updated implementation of Turbo Boost, and maintains Hyper-Threading support.
Core i5 includes the same on-board PCI Express subsystem and dual-channel integrated memory controller. It employs Intel’s improved Turbo Boost (though it’s slightly less aggressive than i7’s). What it lacks, however, is Hyper-Threading—apparently a noteworthy-enough capability to turn an i7 into an i5. Of course, descending the stack also results in lower base clock rates.
The Making Of A Core i5/i7
Architecturally, most of what you get in a Core i5 or Core i7 processor is borrowed from technology already found in Intel’s LGA 1366-based Core i7 and Xeon 3500-series processors. The Lynnfield die is different from Bloomfield though, estimated at 774 million transistors packed into 296 square millimeters (versus 731 million in 263 millimeters for the first Core i7s). More than 400 million of those transistors make up the CPU's cache.
As with Bloomfield, Lynnfield is a monolithic design divided into four cores (execution pipelines, L1 data/instruction cache, TLBs) and the uncore (L3 cache, integrated PCI Express, the memory controller, QPI, and the PLLs). The power for these two “halves” remains separate, independently adjustable in your motherboard's BIOS.
Each of the four cores retains its 32KB L1 data cache (still 8-way set-associative), 32KB L1 instruction cache (still 4-way set-associative), and 256KB L2 cache (you guessed it—still 8-way set associative). An inclusive 8MB L3 cache 16-way set-associative) should look familiar as well.
With nothing really new to report in the cores themselves, we move to the uncore, where Intel has added PCI Express 2.0 connectivity, axed a single memory channel, dropping the total to two, and altered QPI.
- Introduction
- What’s In A Name?
- QPI, Integrated Memory, PCI Express, And LGA 1156
- Intel’s Turbo Boost: Lynnfield Gets Afterburners
- Hyper-Threading: Differentiating Core i7
- Memory Architecture: Does Losing One Channel Hurt?
- P55: The Chipset’s Responsibilities Dwindle
- Windows 7: Microsoft Listens To Intel, Finally
- Test Setup And Benchmarks
- Benchmark Results: Synthetics
- Benchmark Results: Media Apps
- Benchmark Results: Productivity
- Power Consumption
- Conclusion



There is sooo much to learn and there is so much information here.... I feel confused!!
Since when has the I7-920 become an extreme?
Now the i5 750 on the other hand is great performance at a great price, and would certainly be the budget gamers new weapon of choice.
I currently have an i7-920 setup which is my main rig and am very happy with it and not at all upset to the see the 870 outperform it (since the 870 would cost me twice as much). I also have had an i5 750 setup now for over a week (the 1156 processors and motherboards have been available here in Australia for nearly 2 weeks now) and it is an amazing processor for the price of it.
So what am I trying to say? 1366 is still a good platform for the top end of the market. The i5 are fantastic new processors for their price, and the 1156 i7's are just confusing and I'm not really sure who they are going to appeal to? I could understand it if Intel launched the 1156 i7's in 6months time when alot of users are already using the 1156 platform and are looking to upgrade their CPU without a new mobo. But to anyone looking at getting a 870, just get an 920 and use the extra cash on the mobo and ram to go with it.
I would prefer a bench with HD4890. They scale better in CF.
There is sooo much to learn and there is so much information here.... I feel confused!!
This will also compel AMD to bring some more value to the market. Nice article.
http://www.fileden.com/files/2008/3/3/1794507/Turbo.zip
It uses the method that Intel recommends in their November 2008 Turbo White Paper.
Since when has the I7-920 become an extreme?
The power readings are for the whole system, not just the CPU. And their readings are a bit higher than yours because their video cards are almost certainly more power-hungry than yours, and they have a quad-core cpu, running significantly faster than your dual-core (4 cores at ~3Ghz vs. 2 at ~2Ghz, which SHOULD use more power?)
hey guys some tests done at the same cpu speed would be helpfull! thx!
Who was "worried"? It would've been AWESOME (although not to expect of Intel) if the lower-price platform would've outperformed the high-end item.
Typo--thanks for the catch evolve. Pulled that table from a previous review and missed the Extreme!
When you set up an i7 system you turn off the HT and turn up the speed! Turning off a core might even be an upgrade for some. But i agree, the i5 is really a good plateform the mid-mid high level people and at a lower price.
above - too long for intel? for main stream? you could buy a 8400 and run it 3.8 in any system and it rocks.
people have to learn that overclocking is not what it once was, intel does not build all that into the procesor and chipset for nothing so use it! core 2 is still a good main steam system, abit, no upgrading
Great read, by the way
All the mixed rumors were really misleading
http://bit.ly/Lynnfield
And a side-by-side comparison with all the key stats are here:
http://bit.ly/LFDcomparison
AMD is feature packed, Intel is feature lacked.
Intel make good chipsets yes, Intel make good reliable boards (proper intel boards) yes, intel make good CPU's yes.
But Intel have worthless motherboard line ups.... I am happily an AMD fan, I will take my Phenom II with the slower speed for the quality of board I can buy to run it.
Intel & Motherboards = Fail.
Until they improve there, numbers mean zero to me. Why pay more when you get less?
PS. We used to sell all Intel at my work, we now sell 99% AMD. Price, value as a packaged. If Intel had better feature motherboards things might change until then. AMD builds a platform not just a CPU.