I wanted to see exactly what processor I had as the P.C insisted on it being a XP1500+ when I detected it automatically. I had been told to check the serial number on the processor itself to confirm what processor I actually had. I set about removing my fan - I actually had to disconnect everything to get to it including removing the Mobo from the case. I reassembled everything but the P.C wont boot. One LED lights up (a yellow one) but when the power button is pressed nothing happens at all. Is this just me wiring the thing up wrong - an ideas on specific things to check - or have I done something worse - like burnt out a component. I was fairly careful to ground myself before touching the inside of the P.C so I hope this isn't the case. Thanks in advance, SeK 612

Seems to be any problem, since you took out the mobo, the only way to see what is wrong, is take everything out again, and go over it very carefully, making sure you put everything where they belong. Piece by Piece... I know that doesnt help, but you'll learn in the process Good Luck!