Thx for the glxgears and yanc tips.

--BTW, I replaced my ancient Riva TNT2 card with a Geforce4 MX440, and in both Linux + Win everything works perfectly. I did reinstall the Linux driver JIC, but not sure if it's absolutely necessary.

@Dave - did you follow all of nvidia's directions when installing the drivers? You have to comment out stuff like this in /etc/X11/XF86Config-4:

## Load "GLcore" # xxx 2003.0528 Removed for nvidia
## Load "dri" # xxx Removed for nvidia
.
.
.
# Driver "nv" # xxx Removed for nvidia
Driver "nvidia" # xxx 2003.0528