Graphics Cards

[konschi]

So today my PC suddenly turned off. After starting it again my monitor said no signal detected. I put the HDMI cable in the motherboard port and restarted. Its working with onboard graphics card. I also tried another card. Also working. Tried dvi cable on my card. Not working.
Fans are also not moving when starting. Unsure if they should do.

[arcticwind]

Try putting the GPU in another computer. 

Was there any kind of a power fluctuation before it stopped working?

Use a power supply tester or multimeter to test the power supply.

Is the PCIE slot enabled?

Are the any scorched marks / burns on the GPU?