4 Replies Latest reply: Sep 7, 2008 8:30 AM by The hatter
Lofty Becker Level 1 Level 1 (5 points)
Recently my Mac Pro has, at apparently random times, rebooted itself. I don’t think it’s a power problem (I have a UPS, though maybe that’s failing; but “restart automatically after a power failure isn’t checked, so that shouldn’t be happening).

What should I be looking at, or for, to try to figure out where the problem lies? Logs? Software? Hardware checks? Logs (which ones?) I’d like to avoid just taking the computer in for repairs, since the problem is intermittent enough that I’m afraid I might just lose it for a couple of weeks with no help (and I do need it to work).


Mac Pro 1,1, 2.66 gHz, Mac OS X (10.5.4)
  • The hatter Level 9 Level 9 (60,880 points)
    I would begin with Apple Hardware Test and resetting the SMC, then unplug and remove every cable and device except to use monitor, keyboard and mouse.

    Repair your system disk and backup. Even try with a fresh system, erase the hard drive (not just the system partition) is usually one and only way to rule out software.

    I would at least delete the /Library and /System/Library /Caches folders.

    Try with a Safe Boot which doesn't load every extension or process but if it doesn't happen often enough isn't acceptable.

    Monitor the system with Activity Monitor, temperatures (iStatPro). System Profile has information about memory, access to logs.

    If your UPS battery is aging or is under 1200VA, that might.
  • Lofty Becker Level 1 Level 1 (5 points)

    I’ll try some of that immediately (reset the SMC, Hardware test, deleting some of the caches), and try working with a Safe Boot some morning (recently it’s been happening regularly between 8:00 and 8:30). I’ve been looking at temperatures and other stuff, but nothing strikes my eye about odd temperatures or odd activity in Activity Monitor.

    If nothing else works, I’ll try an erase-disk-reinstall-system-and-software, but I’ve been through that enough times (Mac owners since 1984) to want to avoid it if at all possible. Too much software that requires me to find registration codes, needs online updates, etc.

    (Though it probably would be good for me to clean out some of the stuff that I really don’t have any use for.)

    Thanks again!

  • Lofty Becker Level 1 Level 1 (5 points)

    Turns out it was the UPS after all. Problem seems to have been that it would switch to battery momentarily when the line voltage dropped. Dead battery (not replaceable with the one I had).

    Bought a new UPS.

  • The hatter Level 9 Level 9 (60,880 points)
    Now that was the +one thing+ I didn't think to ask, and I often get blamed for injecting "make sure you have a good reliable 1000VA or above UPS" into answers to troubleshooting - gonna have to keep that in mind.