Last week Intel introduced its highly anticipated Lynnfield processors under the Core i5 and Core i7 brands. Three chips emerged:
| Processor | Clock Speed | Cores / Threads | Maximum Single Core Turbo Frequency | TDP | Price |
| Intel Core i7-975 Extreme | 3.33GHz | 4 / 8 | 3.60GHz | 130W | $999 |
| Intel Core i7 965 Extreme | 3.20GHz | 4 / 8 | 3.46GHz | 130W | $999 |
| Intel Core i7 940 | 2.93GHz | 4 / 8 | 3.20GHz | 130W | $562 |
| Intel Core i7 920 | 2.66GHz | 4 / 8 | 2.93GHz | 130W | $284 |
| Intel Core i7 870 | 2.93GHz | 4 / 8 | 3.60GHz | 95W | $562 |
| Intel Core i7 860 | 2.80GHz | 4 / 8 | 3.46GHz | 95W | $284 |
| Intel Core i5 750 | 2.66GHz | 4 / 4 | 3.20GHz | 95W | $196 |
We tested exclusively with the Core i7 870 and the Core i5 750, the 860 didn't arrive in my lab until after the review went live. I was spending the greater part of a week with AMD at that time and didn't get to testing until this past weekend. Here's the chip:
What makes the Core i7 860 so interesting is that it's priced on par with everybody's favorite Nehalem: the Core i7 920. The 870 has great turbo modes, but it's nearly twice the price of the 860. The Core i5 750 wins in the price department, but it lacks Hyper Threading - part of what makes Nehalem so tasty in the first place. The 860 effectively gives us the best of both worlds, hence the focus on it for today's review.
I had a few mistakes in my original version of this table, but below you can see the turbo modes offered by the 860. They're not quite as nice as the 870, but the chip is also half as expensive. You'll also see that like the 750 you only get a single bin improvement with 3 or 4 cores active, but like the 870 you get 4 and 5 extra speed bins in the dual and single active core situations:
| Max Speed | Stock | 4 Cores Active | 3 Cores Active | 2 Cores Active | 1 Core Active |
| Intel Core i7 870 | 2.93GHz | 3.20GHz | 3.20GHz | 3.46GHz | 3.60GHz |
| Intel Core i7 860 | 2.80GHz | 2.93GHz | 2.93GHz | 3.33GHz | 3.46GHz |
| Intel Core i5 750 | 2.66GHz | 2.80GHz | 2.80GHz | 3.20GHz | 3.20GHz |
I've explained turbo mode in great detail here. In short, Lynnfield's PCU (Power Control Unit) looks at the number of cores active, shuts down those that are inactive, and uses the thermal savings to boost the clock speed of the active cores - all within the operating specs of the processor. Unless you're overclocking, turbo will never compromise system stability in search of greater performance.
| Single Core | Dual Core | Quad Core | Hex Core | |
| TDP |  |  |  |  |
 |  |  |  |
It works very well in practice, particularly with Windows 7. A question that's come up since the initial review is what happens when background tasks kick in. As I mentioned in the "Speed Limits" section of the Lynnfield review, this is something that can prevent turbo from kicking in:
"There's also the issue of background threads running in the OS. Although your foreground app may only use a single thread, there are usually dozens (if not hundreds) of active threads on your system at any time. Just a few of those being scheduled on sleeping cores will wake them up and limit your max turbo frequency (Windows 7 is allegedly better at not doing this)."
One of the features of Windows 7 is that the OS supposedly does a better job of grouping tasks together on a single core to avoid waking up an adjacent core and negating the gains from turbo mode. I'm still working on finding a good way to measure this but from what I've seen initially, Windows 7 tends to do a good job of grouping threads onto one or two cores - meaning we tend to see the 4-bin or 5-bin turbo modes. The other thing to keep in mind is that the processor can turbo up/down faster than the OS can schedule threads, the benefits of turbo are present even while in the middle of executing a task. Remember what dictates turbo is both thermal dissipation and current consumption; the mix of instructions executed varies depending on the task and even during the task, which in turn varies the frequency your core(s) will run at.
The end result is a system that seems to feel more responsive as well as perform better. Of course none of this matters if you're going to be disabling turbo and just overclocking, but I've addressed that scenario in a separate article today :)
And I don't really have a reason for showing this, but I like tables so here's the current quad-core processor landscape:
| Processor | Manufacturing Process | Die Size | Transistor Count | Socket |
| AMD Athlon II X4 | 45nm | 169 mm2 | 300M | AM2+/AM3 |
| AMD Phenom II X4 | 45nm | 258 mm2 | 758M | AM2+/AM3 |
| Intel Core i7 (Bloomfield) | 45nm | 263 mm2 | 731M | LGA-1366 |
| Intel Core i5/i7 (Lynnfield) | 45nm | 296 mm2 | 774M | LGA-1156 |
| Intel Core 2 Quad Q8xxx | 45nm | 164 mm2 | 456M | LGA-775 |
The Test
| Motherboard: | Intel DX58SO (Intel X58) Intel DP55KG (Intel P55) Intel DX48BT2 (Intel X48) Gigabyte GA-MA790FX-UD5P (AMD 790FX) |
| Chipset: | Intel X48 Intel P55 Intel X58 AMD 790FX |
| Chipset Drivers: | Intel 9.1.1.1015 (Intel) AMD Catalyst 8.12 |
| Hard Disk: | Intel X25-M SSD (80GB) |
| Memory: | Qimonda DDR3-1066 4 x 1GB (7-7-7-20) Corsair DDR3-1333 4 x 1GB (7-7-7-20) Patriot Viper DDR3-1333 2 x 2GB (7-7-7-20) |
| Video Card: | eVGA GeForce GTX 280 |
| Video Drivers: | NVIDIA ForceWare 180.43 (Vista64) NVIDIA ForceWare 178.24 (Vista32) |
| Desktop Resolution: | 1920 x 1200 |
| OS: | Windows Vista Ultimate 32-bit (for SYSMark) Windows Vista Ultimate 64-bit |
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Gary Key - Wednesday, September 23, 2009 - link
http://www.anandtech.com/mb/showdoc.aspx?i=3639">http://www.anandtech.com/mb/showdoc.aspx?i=3639 - 1600 C7 on both platforms, 6GB for X58 and 8GB for P55, it does not make a measurable difference in performance compared to the 4GB setups.Wwhat - Sunday, September 20, 2009 - link
Anand does indeed use 1066 RAm for the i920 and 1333 for the i860/870/750, but those are the numbers intel specifies them at as you can see on intel.com, now the problem is that people don't use it with such RAM but with 1600 or higher, and also that if you compare the 2 it would be nice of you also compared them with at least equal speed RAM, and when you would use setup that the average guy that builds his own system then you'd get completely different results.So I guess anand is reviewing for businesses who take what they get on the cheap, pre-made systems with 'stock speed' RAM
Gary Key - Saturday, September 19, 2009 - link
"If you clock them at the same rate, with the same uncore, it's only ugly for the Lynnfield. "That is not the case. Actually, overclocking uncore speeds makes very little if any difference unless your application of choice is SuperPi or one of the older 3DMark benches where you can realize some measurable differences (wow, look I gained 0.84 seconds in SuperPI 32M and 27 points in 3DMark06) in the results.
Anyway, Lynnfield will clock both uncore and memory significantly higher than Bloomfield so I have a hard time understanding your comments about this subject. If you do not like Lynnfield, that is fine, but the continued comments about inferior memory being used or uncore rates or turbo modes (which the 920 is running by the way and is inferior to the 860s turbo mode) is really wearing thin at this point.
I already showed the results with DDR3-1600 C7 and nothing changes at DDR3-2000 C7, except VTT/VDimm is much lower on Lynnfield than Bloomfield for equal memory clocks.
For a daily platform, I would take the P55/860 over the X58/920 any day of the week. It simply performs better in most cases and uses significantly less power to do it. In fact, if based on just SOHO computer usage and typical gaming scenarios, I would take the 790FX/965BE over the X58/920. For just a SOHO non-gaming system, I am going 785G/Athlon II all the way.
For benchmarking, I will go with the X58 platform, but even then you have to ask yourself why. Unless you have been provided with cherry components and have a limitless supply of LN2 for setting records, there is not much point in using this platform now unless you are in the workstation arena where future processor upgrades will make a difference.
The only other advantage is in multi-gpu gaming, where the X58 will make a difference in the benchmarks. However, you will not notice the difference between the two platforms in blind A/B gaming comparisons. I know, I tried it on a few users who own X58 platforms. ;) Once again, the vast majority of gamers do not run CF/SLI so even this small advantage is a moot point for most, especially when you consider the performance of the upcoming GPU releases.
The X58/920 consumes significantly more power and performs about the same if not worse at times than the P55/860. So, unless you have two very specific needs for X58, there are great alternatives available from both Intel and AMD. That is the crux of our message in these articles.
strikeback03 - Monday, September 21, 2009 - link
Gary,you have mentioned a few times that Lynnfield uses significantly less power, and obviously at stock settings that is true. But if additional voltage is needed for overclocking, that advantage would seem to disappear. Do you have any tests done to show both platforms at higher clocks? Or how about both at their maximum clock with turbo still enabled, to see if you can save some power while still getting a similar end clockspeed when needed?
Gary Key - Wednesday, September 23, 2009 - link
We will have an article shortly on power consumption (static) with Lynnfield and Bloomfield overclocked. Just to cut to the chase, Lynnfield wins by a clear amount, even with slightly higher voltages on the CPU.strikeback03 - Thursday, September 24, 2009 - link
Cool, thanks.TA152H - Saturday, September 19, 2009 - link
Gary,Would you care to prove any of this? It looks to me on your own bad benchmarks, you run the Lynnfield at higher voltages and higher uncore.
Where is your proof the Lynnfield can clock the uncore higher? Why did you clock them differently then? Where is your data supporting this?
Your remark about turbo was beneath even you. I never complained about turbo modes, except in the context that people here will overclock, and make them irrelevant. I have said repeatedly, against the bashers, it's a nice technology. But, it doesn't show the architectural differences, which a lot of us were curious about. Did you forget you are supposed to be 'tech' site, not PC Magazine?
I agree with you about power. I've mentioned that a few times. I really like the lower power of the Lynnfield. It's a big advantage. I also would rather use an Athlon based machine for a daily machine, especially with the IGP. I've stated all this. But, for my compiles, I'd rather have an overclocked 920 than a brain-damaged Lynnfield. The same for games.
I'm not too crazy about Anand's benchmarks with the uncore of the Bloomfield running faster. Did you see how there were real differences in the results? 3.5% is not a little when you've only changed the CPU. Part of that is because of the uncore, so it's not really fair to the Lynnfield. I'm glad to finally see you guys showing a difference, but, really, it would have been better with uncore at the same rate.
The memory, it would appear, he's using for the Bloomfield is 1066, that's inferior to 1333.
I would be curious about your video claims. They might be right, but what would be really interesting to try to identical cards, except for memory. My guess is, the inferior setup of the Lynnfield would manifest itself more with smaller memory cards, since you'd have to use PCIe more. I could be wrong, of course, it's just theory, but it would be interesting.
Maybe you guys should stop trying to twist benchmarks to make your point, and just run them to give information. That's the crux of my irritation. The Lynnfield is a good product for a lot of people, and I really like what AMD just did. But, when you do little horsecrap things to manipulate results to illustrate your opinion, that's just wrong. You're not nearly smart enough to think for everyone else; no one person is.
yacoub - Saturday, September 19, 2009 - link
"Gary, Would you care to prove any of this?"Considering most of it is in the existing reviews, how about you go back and read them for yourself? And then take his word for it. Or don't, it's your choice, and your loss if you don't.
Griswold - Saturday, September 19, 2009 - link
You can take this as an offense, you are the idiot here. Always been, always will be.C'DaleRider - Saturday, September 19, 2009 - link
No offense, but you're clearly an idiot. And that is clearly demonstrated by this comment, "Anand uses inferior memory for the i7 920, to try to 'prove' the validity of the brain-damaged P55 platform."What was inferior about the Patriot Viper memory? Care to explain why? I personally think you can't defend that comment on any front, esp. considering it has been shown in testing to be an excellent overclocking selection for DDR3 memory, esp. for the price. It'll do 1600 speeds, albeit with using a CAS 8 setting, but for what it costs, it's excellent stuff.
Grow up, and when you finally move out of your parent's house, maybe you'll be mature enough to lose the teenage "I know-it-all" attitude you possess right now.