ATi Radeon X700 XT review
ATi’s Radeon X800 XT may have stolen the gaming limelight, but with demand far outstripping supply, not to mention their sheer cost, they’re not for everyone. As such, the mid-range is a more interesting battleground, and one that nVidia has laid fair claim to with the GeForce 6600.
Despite being projected to retail at about £40 less, the X700 series looks on paper to be more than a match for the 6600. Both possess eight pixel pipelines, but the X700 boasts six vertex pipes to the 6600’s three. This means the X700 should theoretically have the edge in games demanding more geometry calculations.
The XT on test has a core frequency of 475MHz, with its 128MB of GDDR3 RAM running at 525MHz (effectively 1.1GHz). This is in comparison to the 6600’s 500MHz across the GPU and RAM. Both cards have a 128-bit memory interface, but the X700 lacks support for DirectX 9c. This limits the card to Shader Model 2 and 24-bit floating-point precision, against the 6600’s Shader Model 3 and 32-bit floating-point precision. This may not sound like much of a difference but it will certainly affect the X700’s ability to keep up with the cutting-edge games of next year.
The X700 has no trouble with games of this year though, breezing through our Unreal Tournament 2004 and Halo tests at both 1,280 x 1,024 and 1,600 x 1,200 resolutions. It also coped well with Doom 3, managing 31fps, using high-quality settings at 1,280 x 1,024 – admirable for a mid-range card. Pushing the resolution to 1,600 x 1,200 reduced the frame count to 20. Far Cry managed to cause some strain too. At 1,600 x 1,200 and all settings on high, the X700 replayed our benchmark at 13fps against the 6600’s 30fps.
So, the 6600 outperforms the X700 in our high-strain 3D tests – surprising, given the extra grunt from the six vertex pipes. However, ATi has a trick up its sleeve in the form of its new Catalyst Control Center. Or, more specifically, the new ‘AI’ feature.
Considering that this takes place in software rather than hardware, we were impressed by the results. There was no degradation in image quality, and performance increased across the board – surprisingly so in some tests. Unreal Tournament was 18 per cent faster at standard resolution and Doom 3 sped up by 23 and 35 per cent at standard and high resolutions respectively. Not every test showed such significant improvements, but all performed at least 5 per cent faster. Best of all, this performance boost comes without jeopardising the card through overclocking.
This is a mercy, as overclockers will have to look elsewhere unless they wish to invalidate their warranty. The ATi overclock tool added only 6MHz to the core speed, but didn’t touch the RAM at all; hardly surprising as the copper heatsink doesn’t touch it either, so overclocking the RAM would likely lead to some spectacular failures.
With an estimated price of $199 (£110), this card undercuts the nVidia card by about £40. The GeForce 6600 still has the performance edge, even with the AI turned on, but the X700 looks to be a good mid-range buy.