AMD Radeon HD 6790 review

AMD’s latest graphics card aims for the affordable end of the market. The Radeon HD 6790 is based on a cut-down version of the AMD Barts Pro GPU (as seen in the A-Listed Radeon HD 6850), but its 840MHz core clock speed is faster than most of AMD's current range - and indeed most of the firm's previous generation.

At £105 inc VAT, the HD 6790’s closest competition is the Nvidia GeForce GTX 550 Ti, and in our tests we found the two cards performed very similarly. Both averaged 39fps in our High quality 1,920 x 1,080 Crysis test, though the HD 6790 snuck slightly ahead when we upped the quality to Very High, averaging 25fps to the Nvidia’s 23fps.

The two cards followed the same pattern in our Stalker: Call of Pripyat benchmark. In our Very High test, the HD 6790 averaged 37fps, while the GTX 550 Ti dropped a little way behind with 34fps.

Nvidia did nose ahead when we enabled 8x anti-aliasing in our Just Cause 2 benchmark. With Very High settings, the GTX 550 Ti averaged 33fps against the AMD’s 30fps. Overall, though, these are two closely matched cards.

Board partners will inevitably offer overclocked HD 6790 cards, but we saw only a minor performance improvement from tweaking the internal frequencies. Pushing the core clock up to 920MHz, and raising the memory from 1,050MHz to 1,130MHz, gained us a mere 2fps in our 1,920 x 1,080 Very High quality Crysis test.

One definite strength of AMD's card is its power efficiency. In our tests we saw a maximum temperature of 75°C from the HD 6790, 7°C cooler than the GTX 550 Ti. Our test rig's idle and peak power draws of 112W and 245W with the AMD card compared well to the GTX 550 Ti, which took the system to 107W and 271W.

Despite this more frugal power draw, the Radeon requires two six-pin power plugs rather than the single plug of the Nvidia card, so you'll need to make sure your PSU is equipped with the right connections. The stock AMD cooler is louder than Nvidia’s too – not unbearable but certainly noticeable. Board manufacturers will doubtless offer designs with quieter fans.

In all the AMD Radeon HD 6790 is a worthy competitor to Nvidia’s GeForce GTX 550 Ti, and with a projected retail price of £105 inc VAT it’s at least £15 cheaper. If you can stretch your budget, the significantly faster Radeon HD 6850 can be found online for just £20 more, making the HD 6790 look like a mean compromise. Still, AMD's latest delivers decent gaming on a strict budget, and you can't complain about that.

Author: Mike Jennings