AMD Phenom II X4 975 BE review

Can this aging CPU hold its own against the newer Intel offerings?

AMD Phenom II X4 975 BE
Built on ageing architecture in dire need of an update

TechRadar Verdict


  • +

    High stock clockspeed

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    Decent multi-threading performance


  • -

    Merely mediocre for gaming

  • -

    Limited overclocking headroom

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Another day, another minor variation on a familiar theme from AMD. By now you'll know our equally familiar refrain regarding the circa-2003 origins of AMD's performance PC processors, up to and including the latest Thuban sixcore models. But if AMD's underlying CPU architecture is ancient, even the latest derivatives are getting on a bit.

The Phenom II X4 975 Black Edition is the newest chip in AMD's quad-core Phenom II range, but it uses the same old 45nm Deneb die first seen nearly two years ago.

Okay, we're now up to stepping C3, and a few tweaks have been made along the way, but there's no denying that AMD's chips are woofers well past learning significantly new tricks.

For the record, the 975 ups AMD's quad-core ante to 3.6GHz. That's a fairly inconsequential 100MHz increase on its progenitor, the Phenom II X4 970 Black Edition. The benchmark results are predictable to the point of monotony.

Nevertheless, it's our duty to inform you that the 975 completes the R10 version of the Cinebench 3D rendering test in precisely one minute and one second. Funnily, that's exactly the same result we recorded for the 970, which tells you all you need to know about the 975.

Put bluntly, the performance increase is within the margin of error. As for x264 video encoding, the 975 achieves a thoroughly academic increase from 19.4fps to 19.7fps. We could go on, but you get the idea.

Business as usual

One area where you might plausibly hope for the unexpected is overclocking, but here too the results proved pedestrian. Using an air cooler and stock voltage, our 975 sample isn't interested in running beyond 4GHz. Yup, precisely the same speed our 970 sample achieved.

Tweak the voltage mildly to 1.4875V and 4.2GHz is possible, if not with full stability. Give us a little longer with some of the fine tuning knobs and we reckon 4.2GHz is probably doable without crashes.

Of course, none of the above factors in the price of about £150. If AMD makes the 975 cheap enough, you're not going to care how old its underpinnings are.

That's a problem, because AMD's six-core Phenom II X6 1055T and 1075T are also priced in and around the £150. Even the range topping 1100T isn't that much more expensive.

Meanwhile, the comparison with Intel looks even less favourable. Okay, the new Core i5 2500K is likely to be £30 more expensive, but the plain old 2500 will be very closely matched on price and would absolutely hose the 975 by every possible performance metric. And it throws in a intriguing integrated graphics core, for the sheer panache of it.

Frankly, AMD's Bulldozer chips can't come soon enough. The end is nigh for Phenom II.

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