The Lynnfield Preview: Rumblings of Revenge

Power Consumption

I had to overvolt the sample to reach 2.66GHz and I didn't want to compare power of an overclocked CPU to other standard CPUs, so the table below uses the Lynnfield 2.13GHz chip with HT enabled. I also noticed some odd power readings which may be due to the early nature of the platform I was testing so I posted a range of power consumption values for the load.

In my limited amount of time with the test setups I didn't have any other lower clocked quad-core chips to compare to but these early results look promising. The idle power in particular is most impressive.

Thanks to Nehalem's ability to completely power down idle cores the Lynnfield sample delivers the lowest idle power of any quad-core CPU I've ever tested. I didn't have time to investigate it here but I suspect that in scenarios where only two cores are busy, Lynnfield will offer significant power savings compared to all older (non-Nehalem) quad-core CPUs.

Final Words

It really took me until I reached the very end of writing this article to understand Lynnfield and where it fits into Intel's lineup, but I think I finally get it.

The $284 Lynnfield 2.80GHz chip should be very powerful. If I'm guessing right, it'll be faster than any dual core Core 2 Duo in applications that spawn one or two CPU intensive threads, while being faster than a Core i7-920 in even heavily threaded applications.

The $196 Lynnfield 2.66GHz processor stops from being absolutely perfect by not having Hyper Threading enabled. While it performs very i7-920-like in many cases, highly threaded workloads favor the rest of the LGA-1156/1366 lineup. That being said, not having HT isn't the end of the world; in many cases it's just as fast as it would be with HT enabled.

What Intel has done with the entry level Lynnfield is piece together a Nehalem that's just good enough to compete with the high end Phenom IIs and give you more bang for your buck than the existing Core 2 Quads, while not being too good as to ruin the point of the midrange Lynnfield.

There's also a lot of flexibility in Intel's strategy. Intel could deliver lower clocked Lynnfields and enable HT to be competitive at lower price points. I suspect that the real strength of Lynnfield is in its turbo modes; they will give it the advantage of delivering maximum performance regardless of how threaded your workload is.

Why would anyone want a LGA-1366 system then? I believe there are three major advantages to the LGA-1366 platform for single-socket desktops:

1) Support for Gulftown. You can only get 6-cores from the LGA-1366 platform in 1H 2010, Intel currently doesn't have any 6-core LGA-1156 parts planned.

2) More overclockable CPUs. The best yielding Nehalems (and highest clocked Nehalems) will be LGA-1366 processors. I wouldn't expect any 1GHz+ overclocks from LGA-1156 CPUs.

3) More bandwidth to PCIe slots. I don't see this as a huge advantage today, but there may come a time when having as much bandwidth to your GPUs as possible is important. I'm thinking general purpose GPU computing, DX11, OpenCL sort of stuff. But we're not there yet.

Ultimately I'm going to stick with what I first said on the whole LGA-1156 vs. LGA-1366 topic last November:

"The breakdown seems pretty simple: if you’re the type of person who bought the Q6600/Q9300, then Lynnfield may be the Nehalem for you. If you spent a bit more on your CPU or are more of an enthusiast overclocker, the current Core i7 seems like the path Intel wants you to take."

Lynnfield, today, looks very good. Enable all of its turbo modes and I believe Intel has another winner on its hands. When Nehalem first launched I complained that the move to a smaller L2 cache kept it from significantly outperforming Penryn in some applications and games. With Lynnfield's turbo modes I believe my complaints will be addressed; need better performance in games? Turbo mode solves that. In many ways, Lynnfield could end up being even more significant than Core i7 ever was.

Penryn was always good, Bloomfield was nice to talk about but Lynnfield may end up being the one you marry.