No power on Compaq Evo 320

[Wellens Dave]

I bought a second hand Compaq Evo 320 from an auction after bankruptcy. While starting up the system, I noticed Compaq BIOS password was activated. I shut the system down to investigate how to override this on the internet on another system, but when I started up again after removing the side panel, I got no power at all!! Replacing the power cable does not help. I looked inside, even inside the power supply unit, but no marks of overheating or any other problem. Any suggestions?