radeon mobility 7500 - messed up textures

[printf]

hello.

lately i`ve been ironing out all the problems in my gentoo installation, but something does not seem to work, no matter what i do.
currently using the open source radeon driver for drm and radeon-fb for framebuffer (every used "module" is built into the kernel)
glxgears has ok (1800-2000) fps, glxinfo shows direct rendering correctly, but games with textures seem to be messed up.
namely latest ioquake3 from portage, icculus-quake2 and heretic 2 with latest patch trough wine.
most of the time there is no problem in the menus, games run sorta-ok, but sometimes the textures just start wildly changing (i see faces on walls, console fonts instead of object textures, etc)
i have driconf installed to turn off hardware tcl (it boosted performance), color depth is set to 16, and other settings in xorg.conf
video playback works with vlc with overlay

thanks in advance