I have a Cube that has started to freeze with a loud buzzing noise. It will even do it when the system is still in the dashboard. It's not a bad memory card as it will still freeze when it's not inserted. I'm guess it is heat related as it will load the discs fine until it has run ~10 min. I opened it up and it was spotless inside as far as dust contamination.

Any ideas on what damage to look for? I didn't find any obvious bad areas on the pcb or components.