Intel's Core i7 970 Reviewed, (Slightly) More Affordable 6-core

I ran into an old friend of mine who happens to work for Intel at an industry event last month. We were naturally talking about Intel when he pointed out that the company was doing very well. I agreed, but argued that Intel’s progress was being artificially limited by the fact that it wasn’t facing much competition at the high end.

It’s true. AMD’s entire desktop product line exists below $300, and we won’t see a real push for the high end crown until next year with Bulldozer. Until then, the real competition happens at lower (and arguably more interesting) price points where AMD gives you more cores for less, while Intel offers lower power consumption and better single threaded performance.

The ultra high end is still alive and well, despite the lack of competition in the market. Apple just announced its own dual-socket, 12-core monster that will begin shipping next month. Even Intel will tell you that it’s seeing more interest in the Core i7 980X than any previous Extreme Edition part. And the interest isn’t misplaced.

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As the first 6-core desktop CPU based on Intel’s 32nm Gulftown core, the Core i7 980X was the first Extreme Edition in years to offer more than just a clock speed advantage. You got more cores, a larger L3 cache and virtually the highest clock speeds Intel has to offer. If you run highly threaded workloads, you can’t do any better on the desktop today. Thanks to its turbo modes, you don’t even give up performance in lightly threaded apps either.

The 980X of course carried an extreme price tag at $999. With more competition at the high end we might’ve seen derivative parts offered at lower clock speeds and lower price points. But until AMD delivers Bulldozer the impetus just isn’t there. Instead what we’re left with is a slow moving waterfall.

Early next year (Q1) Intel will introduce the Core i7 990X, a clock bumped version of the 980X. Presumably the 990X will run at 3.46GHz by default, but have the ability to turbo up even higher. The roadmap calls for another clock bump in Q2 depending on what AMD does.

Below the 980X there’s only a single 6-core desktop part for at least the next 6 months: the Core i7 970.

Its unassuming name implies little more than just a faster Core i7, however its $885 (1000 unit quantities) pricetag says otherwise. While the rest of the desktop Core i7 line is made up of 45nm quad-core Bloomfield and Lynnfield processors, the Core i7 970 is a 32nm 6-core Gulftown.

Like the 980X, the Core i7 970 has a 12MB L3 cache that’s shared by all six cores, all on a single 240mm2 die. The 1.17 billion transistor chip runs at a stock speed of 3.2GHz but can turbo up to 3.46GHz if two or fewer cores are active. With more than two active, and assuming no thermal or current limits are exceeded, the chip can run at 3.33GHz. For around $100 off the price of a 980X you’re not giving up much in terms of clock speed.

The uncore (everything outside of the CPU cores + L2 caches) also remains mostly unchanged. The 970 runs its uncore at 2.66GHz (identical to the 980X) but the QPI bus is stuck at 4.8GT/s vs. 6.4GT/s. The difference isn’t something that will appear in real world performance however.

Overall expect to see very close to 980X performance for $100 less. You lose the unlocked multiplier, which may have some overclocking implications, but that’s about it.

The rest of the Gulftown enhancements still apply. We finally get uncore power gating and AES-NI. The former gives us power consumption equal to 45nm quad-core Bloomfield i7s, while the latter improves encryption performance. Both of which we’ve demonstrated in the past.

BIOS Support and The Test

Any X58 motherboard with Gulftown support should work with the 970. As was the case with the original 980X launch, you’ll almost definitely need an updated BIOS to make this work.

Even Intel’s own DX58SO motherboard using the BIOS that originally enabled 980X support needed an update to work with the Core i7 970. Unfortunately you need to do this update before you install the CPU so make sure your board is up to date.

We’ve added the Core i7 970 results to Bench, our benchmark database. The graphs that follow are a subset of those results to keep the article reasonably sized.