Which is the Fastest CPU?

The top of the range Intel Core i7 extreme edition is still the fastest CPU available. We quote the latest February review below, from the UK Computer Shopper magazine, for your information:

INTEL

Core i7-3960X

Extreme Edition

★★★★

£840 inc VAT

From www.aria.co.uk

"The Core i7-3960X Extreme Edition is the first chip we've seen from Intel's new Sandy Bridge Extreme, or Sandy Bridge E, range. It's a six-core 3.3GHz processor with an unlocked multiplier for easy overclocking, and is aimed at power users and enthusiasts.

There will be three processors in the range, all of which require a new socket type, LCA2011, and a new chipset, Intel X79 Express. The specifications are:

Processor cores 6 6 4

Number of threads 12 12 8

Smart cache (Level 3) size 15MB 12MB 10MB

Processor frequency 3.3GHz 3.2GHz 3.6GHz

Multiplier unlocked Yes Yes Limited"

Hey! That's what I call the Fastest CPU!

"The first two have six cores with Hyper-Threading (so the processors show up as having 12 cores in Windows) but the cheaper £480 i7-3930K has 12MB of Level 3 cache. Like normal Sandy Bridge chips, the E series' Level 3 cache is shared between all cores, and each core can grab cache from the pool as it needs it.

A major difference between Sandy Bridge and Sandy Bridge E is that the Extreme chips don't have on-board graphics; anyone spending this much on an enthusiast chip would most certainly have a dedicated graphics card. However, the lack of on-board graphics means you won't be able to use Intel's Quick Sync hardware video-encoding technology.

We tested the Core i7-3960X on an Asus P9 X79 Pro motherboard. In our benchmarks, the processor managed an overall score of 123, helped by a strong score of 128 in the image-editing test and 133 in the multitasking test. Like Sandy Bridge processors, Sandy Bridge E chips can Turbo Boost to run higher than their stock speeds in lightly threaded applications; the i7-3960X increased its speed from 3.3GHz to 3.9GHz when running the single-threaded image-editing benchmark. The processor's six cores also helped in the multitasking test, where the image-editing and video-encoding benchmarks run at the same time as playing a high-definition video.

To check the performance of the individual cores, we disabled all but one core then ran our benchmarks again. With one core active, the processor managed 29 overall, which is exactly the same as when we ran the benchmarks on one core on a Core i5-2500K; this indicates that the Sandy Bridge E has the same performance as a Core i5-2500K with two extra cores.

We were surprised, however, that the processor managed only 105 in the video-encoding test, which is not much better than a £170 quad-core Intel Core i5-2500K, which scores 100. Video encoding has traditionally taken advantage of multiple cores, and the i7-3960X's six cores should give it an advantage. However, as we found in our AMD FX-8150 Bulldozer review (see What's New, Shopper 287), many applications struggle to take advantage of more than four cores. During the video-encoding test, Windows Task Manager showed that the J7-3960X didn't go above 40 per cent usage. Even in the multitasking benchmark, we saw only 40-50 per cent usage.

To really test the processor, we ran two sets of our benchmarks at once, then calculated the average scores. In this double benchmark, the processor hit 100 per cent usage in the multitasking test, and managed 95 overall; far better than the 56 a Core i5-2500K processor managed in the same test and around 30 per cent faster than the AMD FX-8150 Bulldozer chip's 64. If you really want to run multiple intensive tasks side by side, this is the fastest chip we've seen yet.

As expected, the processor overclocks well. We turned the multiplier up to 48 to give a 4.8GHz clock speed, about the same as the highest speeds we've seen on Intel's Core i5-2500K.The stable overclock was helped by the RTS2011LC water cooler (around £70 including VAT) that Intel supplied with the chip, which stayed cool and quiet even with our 1.5GHz overclock. At this speed, we saw 145 overall in our benchmarks, which is the fastest we've seen. However, it's only four points faster than Palicomp's Phoenix i5 Shinobi (see What's New, Shopper 287), which has a Core i5-2500K running at 4.8GHz; again showing that applications struggle to take advantage of six cores.

There's no doubt that Intel's Core i7-3960X Extreme Edition is a hugely powerful processor. However, in real-world tasks it has the same problem as AMD's eight-core FX-8150 Bulldozer processor: current applications struggle to take advantage of more than four cores. This still doesn't stop the Core i7-3960X being the fastest processor we've ever seen but, unless you're running several intensive applications alongside each other, it's not drastically quicker than the £170 Intel Core i5-2500K, which is much cheaper and requires far less expensive LGA1155 motherboards. The Sandy Bridge Extreme is the ultimate processor, but most people will rarely need that much power."

Our view is that AMD's latest processors may be the fastest CPUs for games at a budget price, but it is clear that Intel has the best processors for all round performance.

Fastest CPU Review SUMMARY

"VERDICT: Hugely fast, but few people regularly run enough applications at once to need a processor with this many cores

PROCESSOR: Six cores running at 3.3CHz,

LCA2011, 100MHz, 6x 256KB L2 cache,

15MB t3 cache, 130WTDP, three-year

RTB warranty

PART CODE i7-3960X

DETAILS www.intel.com"

See the full review at www.computershopper.co.uk/