This error may be due to overheating, but first I would get the correct 64bit driver for the card and then try it again.
Make sure your graphics card is clean, blow out the fan and cooler with a can of compressed air.
You can test the card with this software.
http://www.ozone3d.net/benchmarks/fur/
FurMark Setup:
- If you have more than one GPU, select Multi-GPU during setup
- In the Run mode box, select "Stability Test" and "Log GPU Temperature"
Click "Go" to start the test
- Run the test until the GPU temperature maxes out - or until you start having problems (whichever comes first).
NOTE: Set the alarm to go off at 90ºC. Then watch the system from that point on. If the system doesn't display a temperature, watch it constantly and turn it off at the first sign of video problems. DO NOT leave it it unmonitored, it can DAMAGE your video card!!!
- Click "Quit" to exit
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These instructions for using Prime95 may help, they are a bit more simplified. But first install the temperature software (post 29) and set it to display the temps in the taskbar. Then run the tests again.
http://www.sevenforums.com/tutorials/100352-cpu-stress-test-prime95.html