I have experienced the same problem
I am working with Suse 10.0 in a Compaq Presario SR1495ES
Processor AMD Athlon 64 3700+ 2.2 GHz
Chipset ATI Radeon XPress 200P
Video Nvidia 6200 TC
NVIDIA-Linux-x86_64-1.0-8756 freeze the system when I start
graphical session some times after 5 minutes of work and some times
after 20 minutes but always I have to shutdown with
the power button.
The problem also exists with previous versions of the driver (8178, 8174 and 7676).
More than 8 month working with the computer and any solution for Nvidia driver, Suse driver works fine but without GL support.