This week I bought a 650w power supply unit for my pc because my old one gave a very loud click noise and the (not very secure) left panel of the case was blown outward by about 1/2 cm! I just about managed to install it by guessing which plug goes where because ALL the plugs and wires in the new one are black and those on my old one seem to be colour coded in some way. on top of that, I thought the 20+4 plug wouldn't fit into the board as the clip seemed to be in the wrong place and the plug had an empty pin-hole which is in a different place to the one on the old 20+4 plug. On top of that there was a four-pin socket on the mobo and NO 4 pin plug on the power supply. I thought I'd have to send it back, but after struggling to get the screw holes lined up with the holes in the case and finally tightening the screws, I did manage to get the 20+4 plug in (by pushing the top end in first, and finding out that the new psu COULD fit into the 4 pin socket as there was a "4+4" pin plug which could be split. So I managed to get it working.
Some time later I looked at thew "Real Temperature" program and it said my two cores were in the upper 50's. EEEK! One is usually at 43C and the other at 37C, I noticed the CPU fan was not turning!
So I did a big switch off and took the side of the case off and it seemed that the fan was being blocked by the cable that had the "4+4" plug on it, so I re-routed it, and now the pc seems to be working well enough.
Having said that, I've yet to try the dvd drive.