The Witcher Gameplay and Performance Guide

The editors at [H] Enthusiast have put together a six-page "Gameplay and Performance" guide for CD Projekt's The Witcher. If you're interested in seeing how the game performs on different video cards or are just looking for some tips on tweaking the game, it might be worth a look. If you don't care about all of the little technical details, here's an excerpt from their conclusion:
The Witcher performs surprisingly well, considering the depth of detail found in the rendered game world. This is thanks in part to the relative old age of the underlying graphics technology, the BioWare Aurora 2007 engine. The outdoor scenery easily rivals, and in some ways surpasses, that found in Oblivion, the old gold standard for outdoor eye-candy. But The Witcher does it more efficiently. You would be hard-pressed to play Oblivion at 1600x1200 with maximum in-game settings on a sub-$200 video card, but The Witcher accomplishes this feat easily.

Using the in-game settings, Anti-Aliasing is limited to 2X MSAA, but only if you have at least 512 MB of video memory. While anti-aliasing does help smooth the final rendered image, the overall benefit is not as great as in some other games. Players that are acutely aware of aliasing will want at least a GeForce 8800 GT 512 MB video card, but for those less sensitive, a Radeon HD 3850 is more than adequate. Gamers with smaller monitors (limited to 1280x1024 or lower) can easily get great performance and an excellent gameplay experience out of a Radeon HD 3850.

In terms of overall value for The Witcher, we have found that the NVIDIA GeForce 8800 GT 512 MB video card is the best value out of the 4 we tested. It provided us with what was essentially the same experience as its much more expensive sibling, the GeForce 8800 GTS 512 MB, and it provided us with a consistently better experience than either of the ATI GPU based video cards tested here.