Intel's Core i7 870 & i5 750, Lynnfield: Harder, Better, Faster Stronger
by Anand Lal Shimpi on September 8, 2009 12:00 AM EST- Posted in
- CPUs
Final Words
I'll start this conclusion with what AMD must do in response to Lynnfield. The Core i5 750 is a great processor at $196, in fact, it's the best quad-core CPU you can buy at that price today. In nearly every case it's faster than AMD's Phenom II X4 965 BE, despite the AMD processor costing almost another $50. Granted you can probably save some money on an integrated 785G motherboard, but if you're comparing ~$120 motherboards the AMD CPU is simply overpriced.
Lynnfield (top) vs. Phenom II (bottom)
Luckily, the solution isn't that difficult. AMD needs to lower prices. The problem is that AMD has too many products below $200 already. The Phenom II X3 and X4 series both exist below $200 and rumor has it that AMD is also going to introduce a quad-core Athlon II somewhere down there. Lynnfield's arrival causes a lot of price compression on AMD's side. The most AMD should sell the 965 BE for is $199, but if it is to remain competitive the chip needs to be priced much lower. That doesn't leave much room for other AMD CPUs. On the bright side, this could force AMD to simplify its product lines again (similar to what it has quietly been doing already).
The next thing that the Core i5 750 does is it finally ends the life of LGA-775. Just as was the case with AMD, the Core 2 Quad Q9650 is easily destroyed by the Core i5 750 and at a lower price. With significantly lower motherboard costs than the LGA-1366 chips, the Core i5 750 can actually compete in the high end LGA-775 space. It's only a matter of time before the sub-$200 LGA-775 parts are made obsolete as well.
Lynnfield power consumption is just excellent, these are the most power efficient quad-core CPUs we've ever tested. They use less power at idle than similarly clocked dual-core processors and under load they deliver better performance per watt than any of their closest competitors. Later this year we'll see 32nm dual-core Westmere start to ship for notebooks. I don't have performance data but I'd expect that early next year will be the perfect time to buy a new notebook.
Can you tell that I like the Core i5 750? Again, at $196 you can't find a better processor. Intel did its homework very well and managed to deliver something that kept AMD in check without completely upsetting the balancing of things. There's no technical reason that Intel couldn't have enabled Hyper Threading on the Core i5, it's purely a competitive move. A Core i5 750 with HT would not only defeat the purpose of most of the i7s, but it would also widen the performance gap with AMD. Intel doesn't need to maintain a huge performance advantage, just one that's good enough. While I'd love to have a 750 with HT, I'd still recommend one without it.
The Core i7 870 gets close enough to the Core i7 975 that I'm having a hard time justifying the LGA-1366 platform at all. As I see it, LGA-1366 has a few advantages:
1) High-end multi-GPU Performance
2) Stock Voltage Overclocking
3) Future support for 6-core Gulftown CPUs
If that list doesn't make you flinch, then Lynnfield is perfect. You'll save a bunch on a motherboard and the CPUs start at $196 instead of $284. We didn't have enough time with our Core i7 860 to include performance results here but my instincts tell me that at $284 that'll be the Lynnfield sweetspot. You get excellent turbo modes and Hyper Threading, without breaking $300.
Speaking of turbo, I'd say that Intel is definitely on to something here. The performance impact was small with Bloomfield, but turbo on Lynnfield is huge. My tests showed up to a 17% increase in performance depending on the workload, with most CPU-influenced scenarios seeing at least 9 or 10%. The turbo mode transitions happen fast enough to accelerate even simple actions like opening a new window. OS and application responsiveness is significantly improved as a result and it's something that you can actually feel when using a Lynnfield machine. It all works so seamlessly, you just always get the best performance you need. It's like Intel crammed the best single, dual and quad-core processors all into one package.
Perhaps that's what kept me from falling in love with Bloomfield right away. It was fast but in the same way that its predecessors were fast. If you didn't have a well threaded application, Bloomfield wasn't any better than a similarly clocked Penryn. Lynnfield's turbo modes change the game. Say goodbye to tradeoffs, the Core i5 and Core i7 are now fast regardless of thread count. It speed that is useful, it speed that you can feel, it's what truly makes Lynnfield the best desktop microprocessor of 2009. It's not just faster, it's smarter, it's better. It's why today's title borrows from Daft Punk and not Star Wars; it's not more of the same, it's something futuristic and new.
Lynnfield shows us the beginning of how all microprocessors are going to be made in the future. Even AMD is embracing turbo, we'll see it with Fusion in 2011. Extend turbo to its logical conclusion and you end up with something very exciting. Imagine a processor made up of many different cores, large and small, CPU and GPU. Each one turning on/off depending on the type of workload, and each running as fast as possible without dissipating more heat than your system can handle.
My only two complaints with Lynnfield are that the chips do require additional voltage (above stock) to overclock and of course the lack of Hyper Threading on the Core i5. It doesn't ruin the processor, but it gives us something to wish for.
Our work is never over.
Facebook
Twitter
RSS
343 Comments
View All Comments
nikrusty - Wednesday, November 18, 2009 - link
With this article Anandtech is Harder, Better, Faster Stronger.Seriously AWESOME ARTICLE! It cleared many of my doubts FLAT OUT! Now I know i5 is the way to go especially becoz I dont care about overclocking and just want good gaming performance...nothing screamingly extreme. Budget + Performance always keeps you level headed.
shiro - Wednesday, October 21, 2009 - link
what is that monster hoop of death heatsink that's on page 3? lolEeqmcsq - Saturday, September 19, 2009 - link
I asked a similar question in one of the other articles, so pardon me if this sounds repetitive.According to the Turbo charts, the slowest Turbo speed is higher than the stock speed. Why is that? For example, why not just make the 750 a stock GHz of 2.8 GHz instead of 2.66GHz?
Eeqmcsq - Saturday, September 19, 2009 - link
Argh, please ignore. Replied using the wrong Firefox tab.The0ne - Tuesday, September 15, 2009 - link
Clear up what you're trying to show on the graphs please. You're getting more FPS at max setting than at min settings? Label the graphs like you did with the others please. With the others I can just look and understand what you're doing. With these, I'm scratching my head.The0ne - Tuesday, September 15, 2009 - link
Ah, turbo mode represented in FPS >.>'kkara4 - Monday, September 14, 2009 - link
over at bittech.net, they are saying that it is more worth it to go for the i7-920, if we are considering anything above the i5. this is a conflicting story, since anand is recommending the lynnfields. anand or anybody else for that matter could you please see their articles and tell me what they have done wrong? (or perhaps you guys failed to see something). Your article explains things in great technical detail which i can understand since i have studied microprocessors, hence i am more inclined to go for lynnfield. anyway if someone could cross check that would be goodmapesdhs - Tuesday, September 15, 2009 - link
If I've understood Anand's analysis correctly, the conclusion is that,
for application mixes which involve a lot of single and/or dual-threaded
codes, and assuming one is not interested in high-end SLI/CF setups
or hard oc'ing all 4 cores all the time for tasks like video encoding
or animation rendering, the 750/860 are better buys because they
will internally push 1-core and 2-core clocks to a higher rate than
occurs with the 920 via the Turbo function, giving better results
than the 920, and of course the 750/860 are cheaper solutions
(although the 860 price is similar to the 920, the mbd costs less
than an X58, from what people say).
So it depends on what you want to use your system for. No interest
in CF/SLI? Running games that don't hammer 4 cores? An i5 750 or
i7 860 makes more sense. Using apps that don't use more than 2 cores?
Again the 750/860 is more logical, especially from a cost viewpoint.
This ties in with the other advantage of the X58 platform, ie. the
upgrade path to 6-core and 8-core CPUs. If this is something that
holds no value to you, then P55 makes more sense.
As always, it depends on what you want to use the system for. The
attraction of the 860 from a more general point of view is that it
also offers good quad-core performance when one does use all 4 cores
without sacrificing the traditional higher-clocks possible with
single or dual core setups when one is only using 1 or 2 cores. It's
the best of both worlds, at least for out-of-the-box functionality
anyway.
However, if one does intend to use all 4 cores almost all the time
(I do) with a strong overclock, then the 920 is a better choice
because of the voltage issue and (IMO) the 6/8-core upgrade path.
Likewise, high-end multi-GPU setups work better with X58.
Given that general usage of a PC rarely uses more than 2 cores, this
is why the 750 and 860 are such attractive options.
As for the 870, despite its 1/2-core speed advantages, the price is
too high IMO. For that kind of money, a 920 makes more sense, paired
with better cooling if one has such a spare budget, or buy a better
GPU setup which, for gaming, is where the real bottleneck lies.
Anand, please correct me if I'm wrong with the above.
Ian.
PS. As always, real-world pricing issues can make a mess of on-paper
technical conclusions. Also, although many games/apps don't exploit
more than 2 cores now, this is likely to change in the near future as
multi-core coding becomes more pervasive in the industry.
mapesdhs - Monday, September 14, 2009 - link
Anand/Gary,
Re your comments about an X58 advantage being the ability to use
later 6 and 8-core CPUs...
I've been planning to build an i7 920 system for video encoding, so
a max oc on all cores is useful to me; from the article I thus infer
the X58 is a better choice.
However, if I did buy such a setup instead of an i5 or i7 860, what
would the cost tradeoff be do you think when the 6-core CPUs arrive
with respect to upgrading? By that I mean, for total processing
throughput, do you reckon a 6-core upgrade would be significantly
cheaper than simply buying a second i7 920 setup? (gfx not an issue)
If not, then the ability to use 6/8-core CPUs later in this context
is somewhat lessened, something that would apply to animation
rendering aswell (ie. extra complete systems perhaps more cost
effective in increased overall throughput compared to upgrading to
more cores). Any ideas? Also, unless the applications used can
exploit more than 4 cores, the later 6-core CPUs won't help. I have
about 1500 hours of material to convert to DivX. Each file is about
40 to 45 minutes (documentary), so converting multiple files on
multiple systems at the same time is very doable.
Given the above, I'm looking forward to more details on how a max
oc'd i860/i870 compares to a max oc'd 920.
At present I'm just using a 6000+ setup to work out the appropriate
format/conversion paths.
Ian.
PS. May I suggest you don't bother replying to those moaning in such
an obviously ludicrous manner about the Turbo mode being active? I
have the distinct impression their posts are designed purely to
irritate. Please don't encourage them. Anyone with any sense will
read the article and understand the salient points you've highlighted
about Turbo mode being an integral function of the chip.
Milleman - Sunday, September 13, 2009 - link
I would say that i5 750 and Pehnom II X4 965 is fully comparable. AMD just have to adjust the pricetag and the price/performance will be on par. Looking at the Gaming rig performance, both i5 750 and Pehnom II X4 965 are well enough for gaming pleasure. I wouldn't shell out my bucks for the more expensive Intel top models. It's such a waste of money, unless you are working with huge video and image editing processes.