Help repairing an Xbox...

My XBox did the power on twice then FRAG, chip fixed it. If the MCPX is at fault you should put a heatsink on it. If you want to increase the fans speed yank the ground wire and solder it to the side of the metal shielding, it will get a voltage boost.

If you didn't manage to get the GPU sink off, leave it on for 30 minutes then gently twist back and forth. Make sure to clean all of the gum off otherwise AS will do no good.