PowerMac G5 clicking noise but no power

Hello everyone,

I acquired a PowerMac G5 with a bad power supply. I just replaced it with a working one from eBay, however when I plug the power cord into the back of the machine I hear a clicking noise and a white light over the power button flashes for a quick second. When I press the power button nothing happens. The clicking noise also occurs when I detatch the power cord from the machine. It is a PowerMac 2 Ghz dual processor 7,3. Any ideas on what to do? A video is linked here to show what’s going on.

Thank you