Ok so now I have:
tried psu from a different comp with ATX 12V 4 pin thing.
tried taking out everything except GFX card
tried jumping the power switch
And they have all failed miserably trying to get the computer on.
I reckon it's the MoBo.
.Well I'll be lucky if they sell these sota antiques still...
Thanks alot for all your help. If anyone has anything to add, It'll be greatly appreciated. Thanks again...
And again
Kisty