>

I would go with Hammann with
"Make sure, that it is overheating and not a weak/dying PSU."

Many people neglect to realise how important a decent PSU is, and how
major an effect it can have on systems. A dodgy PSU in my experience
can do everything from -CAUSING- overheating, to random shutoffs, and
MURDERING hard drives.
I had one which killed 3 Hard Drives before I realised thats what the
problem was, and the last hard drive was so cooked it didn't even spin
up.

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