ProLiant 1850R PPM Error Message

[Peg70]

Hi --

My 1850R has been randomly rebooting itself every few minutes. The error log says "a CPU power module has failed, system board, socket 2." The problem is that there's no PPM in socket 2! I have only one processor and one PPM, both in slot 1. I've tried swapping out PPM's, but to no avail. Why do I have a phantom PPM problem?

TIA, all. This is driving me nuts.

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Peg