Following my previous post, where I succed in getting my HD4850X2 to work (sort of) with Xorg (Mandriva 2009.1) using the 9.4 catalyst drivers (following versions won't compile with the 2.6.29 kernel patch I have handy). The open driver won't even boot X11.
I've got a strange Vsync issue : whatever I do and with or without compiz enabled, I can't have vsync enabled in my main X11 session. but if I open a new DISPLAY with another running X server in it, I have vsync working (example : sdlmame, mplayer...) and get pixel perfect tear free scrollings.
So my question would be : WHY is it working in the secondary display and not the main one ?