Intel Core i7-980X review

Darien Graham-Smith March 15, 2010

£810

Price when reviewed

Intel’s Core i3 and i5 desktop chips have already demonstrated that the new 32nm process has clear benefits, and now the Core i7-980X (codenamed Gulftown) brings that die-shrink to the top-end LGA 1366 platform. The result is a chip so powerful that, reportedly, Intel originally intended to call it Core i9.

With a stock clock speed of 3.33GHz the i7-980X matches the 45nm Core i7-975, hitherto the fastest model in the family, and where previous i7s have been quad-core parts, the new chip incorporates six physical cores. Thanks to Hyper-Threading, that means a single CPU can service twelve processes at once. The chip’s L3 cache has grown proportionately too, to 12MB.

What’s more, Gulftown is far less conservative than existing LGA 1366 processors when it comes to Turbo Boost, aggressively clocking individual cores up to 3.6GHz at the drop of a hat, then slashing them down to 1.6GHz when idle – keeping total idle power draw down to a bearable 108W on our test system.

That’s a trick learnt from Intel’s 32nm Westmere platform, and Westmere’s new hardware AES encryption and decryption instructions are here too, although the LGA 1366 platform doesn’t currently support any sort of integrated graphics.

Need for speed

The real focus, though, is on performance, and in our desktop benchmarks the i7-980X achieved a very creditable 2.23, nosing ahead of the i7-975 which scored 2.19. Unsurprisingly, the new CPU fared particularly well in the multitasking test, with a stellar score of 2.75, but even this doesn’t reflect the full power of Gulftown. With so many cores on hand, this result was achieved using less than 30% of available processing capacity.

Once again, Intel has broken its own record and produced the fastest CPU we’ve seen.

A better indicator of the true potential of the i7-980X is our 3ds Max test, since this application is specifically optimised for multi-core processing. Here, the 103 seconds taken to produce our scene represents a score of 3.04 against our reference PC. With all twelve virtual cores being taxed at once, power consumption for the whole system hit 217W, versus a peak of 173W in our multi-applications test.

Since the i7-980X is a multiplier-unlocked Extreme Edition, performance can be pushed yet higher by increasing the chip’s range of available operating frequencies in the BIOS, and the 32nm design gives plenty of headroom to do so. With a stock cooler, we were able to raise the maximum Turbo Boost speed to 4.14GHz, yielding a magnificent overall benchmark score of 2.59 (including a rather impressive 3.15 for multitasking). Once again, Intel has broken its own record and produced the fastest CPU we’ve seen.

The cost

Such prestige inevitably comes at a price, and in the US Intel anticipates selling these chips in bulk for $999 each. Early UK pricing has come in at £689 plus VAT. For most of us that’s impossible to justify when, for everday use, a 3.4GHz AMD Phenom II delivers five sixths of the performance for around one sixth of the price.

Indeed, for everyday use a six-core processor makes no sense at any price: despite the onward march of hardware, most modern desktop applications simply can’t make use of this many threads. That, along with the price, destines Gulftown for a specialist workstation role, rather than a general-purpose desktop.

So, the i7-980X isn’t a realistic purchase for most of us, but it is still a great demonstration of processor potential, and a salutary hint at the sort of power that can be expected to trickle down into the mainstream over the next few years.

Specifications
Cores (number of)	6
Frequency	3.33GHz
L2 cache size (total)	3.0MB
L3 cache size (total)	12MB
FSB frequency	N/A
QPI speed	6.4GT/sec
Thermal design power	130W
Fab process	32nm
Virtualisation features	yes
Clock-unlocked?	yes
Performance tests
Overall application benchmark score	2.23