Hi!
I´m having a similar problem, I installed Linux Mint 12, everything is doing fine but I can´t enable visual effects.
I used to have Linux Mint 7 and I never had a problem.
Help please!!!
jean-christophe@Teahupoo ~ $ inxi -G
Graphics: Card: nVidia C73 [GeForce 7100 / nForce 630i]
X.Org 1.10.4 drivers nvidia unloaded: fbdev,vesa,nouveau Resolution 1360x768@50.0hz
GLX Renderer GeForce 7100 / NVIDIA nForce 630i/PCI/SSE2 GLX Version 2.1.2 NVIDIA 173.14.30
jean-christophe@Teahupoo ~ $ compiz-check
Gathering information about your system...
Distribution: Linux Mint 12
http://www.linuxmint.com/rel_lisa.php Desktop environment: GNOME
Graphics chip: nVidia Corporation C73 [GeForce 7100 / nForce 630i] (rev a2)
Driver in use: nouveau
Rendering method: Nvidia
Checking if it's possible to run Compiz on your system...
Checking for texture_from_pixmap... [ OK ]
Checking for non power of two support... [ OK ]
Checking for composite extension... [ OK ]
Checking for FBConfig... [ OK ]
Checking for hardware/setup problems... [WARN]
Something potential problematic has been detected with your setup:
Warning: Detected driver is not on the whitelist.
Would you like to know more? (Y/n) y
Your driver is not widely known to work with Compiz and thus may be
blacklisted on certain distributions.
You can skip this blacklist -- but keep in mind that you did so.
Do not complain if you encounter any problems with Compiz afterwards.
Do you want to skip blacklist checks by Compiz? (y/N) ^C