Well, i did a fresh install of Mac OS 10.6.3 with the retail DVD, got the 10.6.8 update, and then, got Lion from App Store.
My Card (Sapphire HD5770 Vapor-X 1002:68b8) works well, with full QE/CI, Full resolution, Two monitors on it (One HDMI and one DVI) and so on.
But i have a issue with it...