Gamecube powering off randomly

[Paul.str]

I am having a problem with my precious gamecube.

It is a Japan-made NTSC DOL-001 with IPL 2.0 and power switch v1.
It is completely stock. I have done no modifications at all.
It was opened one to replace the fan. I put in a fan from a chinese 001.


The problem arises and 2 ways:
After playing for about 40 minutes, the gamecube just shuts off. The power LED goes off, the video cuts out, but the fan keeps running.
It requires me to rapidly cycle the power to get video back, but always dies after 5 more minutes of play.
It works fine after cooling down.

Sometimes, when I get it out of its box, it just won't turn on. It makes a high pitched noise, the fan starts going, but the video and power LED do not turn on.
I have to cycle the power rapidly to alleviate the problem.
The gamecube is usually good for a while after this happens.

Any idea why this happens? The gamecube doesn't feel hot after this happens and the new fan didn't help.
I don't want to lose my 'cube. I've had it for nearly a decade and am pretty attached to it.

[wii_HD]

The hardware guys should have a good idea.

My guess is the thermal paste has dried out.

[Ashen]

Yep, sounds like its overheating to the point where the thermal protection circuit is kicking in. I'd pull it apart and check the thermal pads between the heatsink and procs. It could also be a failing A/C adapter.

[HomelandReloaded]

I would check the temperature of the heatsink with a digital thermometer before taking it off to check the thermal pads. It's awkward to remove and then you've got to get some replacement pads. I would check for dust, fan speed, and A/C adapter before removing the heatsink.

[Drakon]

Thank god the design has you bolt the heatsink to the rf shielding underneath.