Hi, newbie here to the forum, and the first time on a Mac in over 12 years. I'm sure I'll have many questions that can be categorized as "dumb", and this will be the first one. My Mac Pro (which I've had all of 2 weeks) will run the fan at what seems to be full tilt starting about 30 seconds after I shut it off (not when I put it to sleep). The 2 times this has happened, I could not turn the Mac back on while the fan was blowing like this, and had to actually turn the UPS switch off, then back on, at which time the fan would had stopped running and I could turn the computer would now boot back up. The fan ran once like this 45 minutes before I hit the UPS master switch. I couldn't even find where to ask this question of Apple. So, does anyone here know: is that the way the thing is supposed to work? Why can't I restart the machine while the fan is blowing? BTW, our computer doesn't get heavy duty use, so the fan has never ran that fast while we were actually using it...only after it goes through the shut down sequence.