According to steamer :
--If you're using a UPS check the battery. That turned out to be the
problem when my system started puking at random..

Yes -- some UPS models check the battery every so often by
switching over to run from the batteries for a few seconds and
monitoring the voltage during that time.

If the batteries are getting tired, you will loose the power and
reboot.

If the batteries are fine, but you are at the top edge of the
capability of the UPS (or beyond), you will also experience this same
problem. it is better to not exceed 75% of the capacity of the UPS,
though I am currently guilty of running at 86% while I am migrating
everything from an old server to a much newer (and faster) one.

If you have a laser printer hung on the UPS along with the
computer and a large CRT monitor, you could have excess load at least
when the monitor is on and the laser printer cycles on the fuser coil,
so that combination could force a reboot.

Good Luck,
DoN.
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