Sapphire Radeon HD 6850 review

Thanks to the shift in pricing that followed the the AMD HD 68xx series, the HD 6850 has come into its own more in the intervening months. Now available for as little as £132, it's about the same price as the GTX 460, and just about had it pipped to the post in most of our benchmarking suite.

Like the HD 6870 before it, it's based on the same Barts GPU, a reworking of the GPU at the heart of AMD's last generation of DirectX 11 graphics cards, the HD 58xx series. In real terms, though, this card was brought in to replace the excellent HD 5770, despite what the naming structure may have you believe.

For the price it gives fantastic performance numbers, mostly thanks to AMD's driver team. At launch, this card was looking off the pace compared to Nvidia's GTX 460, especially in 1GB trim. Today, though, the driver-level tweaks mean that it outperformed the GTX 460 in all but the Nvidia-favouring benchmarks such as DiRT 2.

The more the merrier

The impressive performance only gets better when you add a second card in CrossFire. Thanks to the ubiquitous nature of CrossFire-capable motherboards, pretty much anyone with a vaguely modern mobo can enjoy AMD's multi-GPU technology.

For a reasonable £264 outlay for a pair of HD 6850s, that's looking like a safe bet for anyone who would have gone for a GTX 460 SLI setup but found themselves stuck with a non-SLI board. In CrossFire, you're looking at the sort of performance that could show up a GTX 580 at the standard resolutions. For this cash, that's incredible.

Benchmarks

DirectX 11 tessellation performance
Heaven 2.5 FPS: Higher is better
Single: 11.6
SLI: 23

DirectX 11 gaming performance
Metro 2033 FPS: Higher is better
Single: 2
SLI: 3

DirectX 11 gaming performance
Aliens vs. Predator FPS: Higher is better
Single: 15
SLI: 30

DirectX 11 gaming performance
Lost Planet 2 FPS: Higher is better
Single: 17
SLI: 31

DirectX 11 gaming performance
DiRT 2 FPS: Higher is better
Single: 39
SLI: 73

DirectX 10 gaming performance
Just Cause 2 FPS: Higher is better
Single: 21
SLI: 41

Being able to top 30fps in Metro 2033 at 1,680 x 1,050, in full DX11 mode, with 4x antialiasing, is little short of astonishing. The GTX 460, while a sterling value proposition, is left lagging behind a pair of HD 6850s, especially in the increasingly-important DX11 gaming benchmarks.

It is a little pricier than the GTX 460, but with the increased number of CrossFire-compatible mobos compared with SLI-certified boards, the HD 6850 pair has to take the win. It's not the overclocking monster the cheaper GXT 460 is, but there's a little more juice you can squeeze out, putting it almost on the same level.

There's also the fact that you can keep adding in more cards all the way up to four-way CrossFireX (should you have a PSU with more PCIe connectors than the great lord Cthulu has tentacles). With the competing Nvidia card, you're restricted to two-way SLI. That may not be a huge problem considering the diminished returns from going above two GPUs, but it still gives you the option to add to an existing setup.

The HD 5850 could cause issues for the HD 6850, performing more in line with the HD 6870s higher up the pecking order. Still, as a bargain board with multi-GPU leanings, the HD 6850 is attractive.

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