kdjac its not the PSU, as i got it changed and still nothing worked.
I cant remember the PSU off hand or the motherboard, but the dimensions of the motherboard are about 245 X 240 mm and its like this one ( with a few less pci slots ):
http://cgi.ebay.co.uk/Abit-KV8-Pro-S...ayphotohosting
It was a packard bell that I bought about 2 years ago from europc.co.uk. It was about 6 months old at the time.
I have a fair idea when it comes to the hardware, bar the motherboard ( obviously ) so i dont mind changing stuff and removing stuff as i have done a lot of it before.