The PSU supplies various voltags and NOT all can be available. Even though the mtrbd. led and PC case(?) led is active, if not all voltage present, no go. Basically, the prudent thing to do is replace PSU with similar or better rated wattage and install. This excludes any possible other source that may have caused the PSU to fail, but PSU's fail usually because they're old or "over-taxed".
Overnight my previously functioning computer (spec below) completely failed to start. "Completely" as in nothing happens when I press the power on button, no beeps, nothing. I've done the obvious stuff with power supply checks but the power appears to be OK. The PSU operating light is on and the motherboard's little green light is on so there is power to the board. It isn't case button failure as I have tried starting it by using a screwdriver over the system power pins on the motherboard's panel.
I know nothing about viruses & was pondering that only a nasty infection of the BIOS could actually prevent the machine from powering up at all. The Virus Forum thought it unlikely, so I've come to more familiar hardware failure territory for help! Should clearing CMOS be my first move? Thanks, L.
[Asus M2N32-SLI DeLuxe motherboard, AMD Athlon 64 X2 CPU, 4Gb DDR2 RAM, Windows XP Pro SP2, self built]