PC Problem

[PhilD]

I have a problem with my PC. It was re-booting itself randomly. By logging on to a website seem to cure this. Then when it was first plugged in the HDD and CD record lights would come on with interference through the speaker for a few minutes and then it would boot up normally. Now the lights and interference do not stop and I cannot boot up the computer. The cooling fan on the CPU (which I've replaced) runs for a few moments then stops. Any ideas?

[j2buttonsw]

Try replacing the power supply unit (PSU).