Everything works with the normal drivers. Monitor is fine(I tried both the configuration for the monitor XFree gives me and the manual of my monitor). I use normal configuration of XFree(dri turned off, etc, etc) and I have NVagp setting and logo on start up turned off.
But I think I found the problem. My dad turned off the function "make video ram cachable" in the bios. I am also trying to change some bios options because I also have problems in windows(locks up on start-up) but I checked my manufacterers site(http://www.xfxgraphics.com
) and it tells me that windows' AGP gart drivers are the cause and I don't have drivers that came with my mobo.