Sapphire Radeon HD 5850 1GB review

The Radeon HD 5870 (see What's New, Shopper 162) is the most powerful graphics card we've ever seen, but for just over £300 you'd be right to expect something special.

For keen gamers on more moderate budgets, the Radeon HD 5850 is a more reasonable buy at £200. It's still a lot of money for a graphics card, but thankfully it's worth every penny.

It may not be quite as powerful as its larger sibling, but it's still mind-blowingly quick. The core clock speed is down to 725MHz from 850MHz and the 1GB of GDDR5 memory runs 200MHz slower. It has 1,440 stream processing units, so it can simultaneously execute this many vertex, geometry and pixel shading operations. That's only 160 fewer units than the HD 5870 has, and a massive step up from the 800 units found on most of the 4800-series cards.

Our benchmarks showed some differences between the cards, but only in the most demanding games. With 88.4fps in our Call of Duty 4 benchmark, the 5850 produced a slightly higher frame rate than the 5870 achieved last month, thanks to a new set of more refined drivers. In our demanding Crysis test, the HD 5850 dropped 8fps compared to the HD 5870. However, it still managed a smooth 42.4fps at 1,920x1,200, proving that it's capable of pleasing results on high-detail monitors.

Apart from raw performance, the HD 5850 has all the features that made the HD 5870 so exciting. It has full support for DirectX 11, which adds tessellation, allowing for more complex models in games, along with a range of new effects. There's also Eyefinity, which lets you connect up to three displays to the card at full-HD resolutions for multi-monitor gaming.

It has all the outputs you're likely to need, with twin dual-DVI, HDMI and DisplayPort. It's 25mm shorter than the HD 5870, but still takes up two expansion slots in your PC. The HD 5850 needs two PCI-Express six-pin power connectors, and ATI recommends at least a 500W power supply. There's support for multiple cards via CrossFire, although we doubt may people will need the extra graphical muscle.

We've never seen a card this powerful at this price before, and it should have a lengthy lifespan thanks to its DirectX 11 support. If you're an avid gamer, we can't recommend it highly enough, but everyone else should consider the more affordable HD 5770 and 5750 cards.