3 Replies Latest reply: Jul 14, 2009 10:39 AM by Feek
Feek Level 1 Level 1 (0 points)
I bought my Early 2008 Mac Pro second hand towards the end of the summer last year and I noticed a couple of times that if I shut the computer down and tried to turn it back on again that it would click when I pressed the power button but not start. I found the only way to make it restart was to pull the power cable out and plug it back in again, then it'd restart. Sometimes I'd have to do this two or three times before it'd start working.

Over the winter, this problem vanished and I thought nothing of it, I don't actually switch the Mac Pro off very often, I normally sleep it.

A couple of weeks ago when it was very warm outside, it did it again but it stopped once the weather cooled down.

Last night, I put the system to sleep and a few minutes later I needed to get back on the computer so I tried to wake it up and it just clicked once and nothing happened. The only way I could get it started was to remove the power cable, wait a short while and plug it back in again.

So it looks to me that whenever the room temperature hits around 25C that my Mac Pro gets grumpy and won't restart. I use iStat Menus and the ambient system temperature still never really gets above 24-25C.

I've got an Apple 8800 graphics card, the default supplied graphics card (can't remember what that is!), 10Gb RAM and four hard drives in the system but to be fair, it did it last year when I only had the 8800, a single hard drive and 2Gb RAM installed.

It's as though a thermal cutout is getting the hump and refusing to start until I pull the power cable and reset everything.

Is this 'normal' behaviour or should I be getting it looked at under Applecare?

Thanks,

Keith.

Mac Pro (Early 2008), Mac OS X (10.5.7)
  • 1. Re: Mac Pro won't come out of sleep or power on - Heat related?
    japamac Level 7 Level 7 (24,390 points)
    Hi-

    What you describe is not normal behavior for any computer.
    25ºC is not hot at all, and should have no effect on the machine.
    The advertised operating temperature range is 10ºC to 35ºC.

    I would use my Applecare if I were you.
  • 2. Re: Mac Pro won't come out of sleep or power on - Heat related?
    The hatter Level 9 Level 9 (58,880 points)
    I think the 5400s take much more than 35C. But ambient you are totally fine. Unless there isn't good airflow out the back and around the system.

    The 8800GT does run warm to hot and some now run hotter and have failed post 10.5.7, plus the fan on the card doesn't kick in early enough.

    The old Radeon X1900 use to be a lot of trouble with heat and dust.

    Electrical and environmental requirements

    * ENERGY STAR configurations available
    * Line voltage: 100-120V AC or 200-240V AC (wide-range power supply input voltage)
    * Frequency: 50Hz to 60Hz single phase
    * Current: Maximum of 12A (low-voltage range) or 6A (high-voltage range)
    * Operating temperature: 50° to 95° F (10° to 35° C)
    * Storage temperature: -40° to 116° F (-40° to 47° C)
    * Relative humidity: 5% to 95% noncondensing

    http://support.apple.com/kb/SP11
  • 3. Re: Mac Pro won't come out of sleep or power on - Heat related?
    Feek Level 1 Level 1 (0 points)
    Looks like it does have a problem, I've made an appointment at the closest Genius Bar tomorrow. I hope they can assist me getting it in from the car as the nearest car park isn't very close to the Apple store!