Sapphire Radeon HD 5770 review

Following hot on the heels of the excellent HD 5850 comes ATI's 5700-series of graphics cards, which comprises the HD 5770 and HD 5750.

Both cards have the same impressive feature list as the 5800-series, so you get DirectX 11 and Eyefinity triple monitor support. However, there are significant architectural differences between the 5700-series cards and their larger siblings.

The HD 5770 has 800 stream processing units. This may be a lot less than the 1,440 found in the HD 5850, but it's the same number as on the powerful HD 4890. The clock and memory speeds are actually higher than those of the HD 5850, but there are other issues. Like many previous mid-range cards, the HD 5770 has a 128-bit memory interface, rather than the 256-bit interface used in more expensive models, which can be a performance bottleneck.

Its performance in our benchmarks was capable but not outstanding. A score of 33.6fps in our demanding Crysis test proves that even the toughest games are playable at high detail settings, but the score is 6fps shy of the HD 4890's, which is currently available for only around £10 more.

The newer card has other advantages, however. Its DirectX 11 support appears to be the key feature, but it's hard to say whether the card is powerful enough to deliver the extra graphical effects that will be included in such games over the next couple of years. The card is cooler, quieter and around 35mm smaller than the HD 4890, and it's less power-hungry, requiring only a single 6-pin power connector rather than the HD 4890's two. It's also capable of outputting digital HD audio.

If any of these tertiary benefits appeal to you, the HD 5770 is a better buy than the HD 4890. However, if you just want straightforward graphical muscle for running todays' games, the older card is a better option, at least while stocks last. We looked at both the HIS and Sapphire versions of the HD 5770 for this test, and they were essentially identical, so buy whichever card you can find for less.