Что выдает, если в терминале делаешь compiz --replace
Вот что:
mckool@ubuntu:~$ compiz --replace
Checking for Xgl: not present.
Detected PCI ID for VGA:
Checking for texture_from_pixmap: present.
Checking for non power of two support: present.
Checking for Composite extension: present.
Comparing resolution (1680x1050) to maximum 3D texture size (8192): Passed.
Checking for Software Rasterizer: Not present.
Checking for nVidia: present.
Checking for FBConfig: present.
Checking for Xgl: not present.
/usr/bin/compiz.real (video) - Warn: No 8 bit GLX pixmap format, disabling YV12 image format
/usr/bin/compiz.real (video) - Warn: No 8 bit GLX pixmap format, disabling YV12 image format