How to power on the Dell Optiplex 980

[Darlene the Queen]

Can't seem to power on my Optiplex 980. the power supply appears to work because I can push the test button and it will partial start up the desktop.

 

[BlacKHawK3]

At what point does it stop working?

This sounds like a OS issue, you may want to look in Tom's troubleshooting guide.