PC failed to get to POST

System description;
3 years old
512 RAM
Gigabyte GA-85648FX MB
DVD ROM
CD RW
FDD
120GB Hitachi Deskstar HDD
XP sp2
No changes in h/w or s/w
Up to date Norton AV

Ok, the problem... Went to start the computer and it failed to Boot. In fact it failed to get to POST I think. ie no beeps, the power light was on (but no-one home ), HDD light was steady (not flickering like it normally does when booting up). Monitor screen was blank but power light was on (ie not in sleep mode). And from there nothing would happen. HDD did not spin up, but both PSU fan and CPU fans were running.

I have disconnected all drives - no change on restart. Changed the CMOS battery - no change. I plugged the HDD into another computer and the drive did spin up.

Is this a PSU failure or a MoBo failure or something more sinister?

 

Thanks. Trying to get my hands on a PSU. Will let you know the result.

 

Yeah, usually when theres no beeps or no harddrive spin-up (besides the fans running) the PSU may be the problem.

 

OK, bad news I'm afraid. I put in the new PSU and there is no change. PC still doesn't make POST and neither does the HDD spin up.

Does this just leave MoBo or CPU as the culprits?

 

Thanks for your help! I'm off to shop for a MoBo....