The latest ATI Catalyst 9.3 drivers now officially support Windows 7. Daily Tech have the full lowdown on this here:
http://game.amd.com/us-en/drivers_catalyst.aspx
You can download the latest ATI drivers from here:AMD's graphics division has released ATI Catalyst 9.3 drivers with full support for Windows 7, including Windows Display Driver Model (WDDM) 1.1 compliance for ATI Radeon HD 4000, 3000, and 2000 series of graphics cards.
All future ATI Catalyst postings will deliver one single unified driver for both Windows 7 and Windows Vista, allowing Windows 7 beta testers the convenience of swapping back and forth between the two operating systems without the hassle of multiple drivers which may have differing builds.
Gaming performance has also been improved for Windows 7, increasing its lead over Windows Vista. Catalyst 9.3 supports the Direct2D API introduced in Windows 7, which could improve everything from ClearType text rendering to hardware-accelerated vector graphics. Improved (e-mail address removed) scores are also promised for ATI Radeon HD 4000, 3000, and 2000 series of graphics cards.
http://game.amd.com/us-en/drivers_catalyst.aspx