first off go to
www.nvidia.com
download the drivers for the nvidia card from there do not use mandrakes drivers
second after you read the read me and run the install you must edit the XF86Config-4 in 2 places
in the modules section add this line
Load "glx"
in the device section change this line
driver "nv"
to
driver "nvidia"
then reboot and all will be well
READ THE DOCUMENTAION FROM NVIDIA PRIOR TO INSTALL
and you must run the installer while x is not running from a console like init 3
also make sure your bios has
assign a irq to pci video set to yes
atokad