Random iMac shutdown

Every couple of weeks, I come home from work and my iMac is off(I leave it on all of the time). This has happened 3 times since I got it in early December. Is this normal?

No, it's not normal but that depends on the power in your home. Power glitches or resets on the line can cause it to shutdown. I strongly suggest buying an UPS (Uninterruptible Power Supply) for the iMac. Or, if you're going to leave it for any length of time, shut it down. UPS units are sold in most stores that have computers and accessories and are not expensive.

Thanks, I'll look for one tomorrow...appreciate your reply. I was under the mistaken(apparently) notion that a power strip was ok but now I realize that is only a source of multiple plugs.

It must have been the power making it go off, I got a new protected power supply right after I posted and it hasn't shut down by itself since. Thanks!!

Thanks for posting back and letting us know.