ubuntu@ubuntu:~$ compiz --replace &
[1] 10511
ubuntu@ubuntu:~$ Checking for Xgl: not present. 
Detected PCI ID for VGA: 01:00.0 0300: 1002:4c66 (rev 02) (prog-if 00 [VGA])
Checking for texture_from_pixmap: present. 
Checking for non power of two support: present. 
Checking for Composite extension: present. 
Comparing resolution (1400x1050) to maximum 3D texture size (2048): Passed.
Checking for nVidia: not present. 
Checking for FBConfig: present. 
Checking for Xgl: not present. 
Starting gtk-window-decorator
/usr/bin/compiz.real (core) - Fatal: No GLXFBConfig for default depth, this isn't going to work.
/usr/bin/compiz.real (core) - Error: Failed to manage screen: 0
/usr/bin/compiz.real (core) - Fatal: No manageable screens found on display :0.0