I had something along these lines come in the shop on Saturday.
Shutting down under any sort of load, one our shop had built about 7 months ago.
Turned out the retail heatsink (Intel Prescott 3.2) was completely blocked.
I literally fired up the compressor, gave it a 20 second blow out, CPU heatsink as well as PSU and graphics card cooler, didn't even connect it up (it was that obvious)
7 months isn't very long for the heatsink to become that blocked, I warned her that she would have to bring it back on a regular basis, FOC of course.
Hers was unusual because of the speed in which the heatsink had got blocked, I can only assume her house is particularly dusty or the tower may have been kept on the floor possibly on carpet which is susceptable to dust and fibre build up.
Martin
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