That's my first post here, hello all 1.My PC Specs: CPU: Core2Quad 6600 MB: Asus P5WDG2 WS Pro (CrossFire) MB Chipset: Intel 975X RAM: DDR2 Patriot Extreme 4GB GPU: 9800GT 512 + 8800GTS 640 SYS: Windows 7 Ultimate x64 2. I've make SLI on CrossFire board with HyperSLI, then I've installed 301.42 Drivers + Different card modded drivers 301.42. 3. Everything works fine, but when I select SLI - Boom bluescreen. I've tried to swap cards, for 8800GTS to be the main one. Then when I select SLI, black screen appears with "_" for about 2 minutes, then all back to windows, but 8800 driver crashed. After reebot, windows stuck on boot screen. 4. Any solution? Is is even possible? p.s. sorry for my bad english.