I have a Mac Pro from mid 2008. Recently, it has done the following:
Also, it will now sometimes just power off completely without warning.
Problem 1: In the morning when I turn it on, on some occasions it will power on for 5 or so seconds, then power right back off again. Sometimes this happens after 5, 10 or even 20 seconds (right in the middle of OS X or Windows boot). This can sometimes happen 10 or 20 times in a row before it will eventually turn on and function normally.
Problem 2: Random power cut off, sometimes at idle, sometimes while browsing, or using any other app. I can't pin it on any one particular function. I know it's not a temperature problem, I have temp monitors on my menu bar and as far as I can see it's been fairly stable in that regard. Most of the time, I can power up the computer again but very occasionally it will revert to what I described in problem 1.
I had it checked out by an engineer who got it running, and ran diagnostic tests on a loop. No problem. Then took it home and problem 1 re-occurs!
One further piece of info, boots up fine if I remove the power cord overnight.
Any advice, or others who have had this problem would be much appreciated.
Also, it will now sometimes just power off completely without warning.
Problem 1: In the morning when I turn it on, on some occasions it will power on for 5 or so seconds, then power right back off again. Sometimes this happens after 5, 10 or even 20 seconds (right in the middle of OS X or Windows boot). This can sometimes happen 10 or 20 times in a row before it will eventually turn on and function normally.
Problem 2: Random power cut off, sometimes at idle, sometimes while browsing, or using any other app. I can't pin it on any one particular function. I know it's not a temperature problem, I have temp monitors on my menu bar and as far as I can see it's been fairly stable in that regard. Most of the time, I can power up the computer again but very occasionally it will revert to what I described in problem 1.
I had it checked out by an engineer who got it running, and ran diagnostic tests on a loop. No problem. Then took it home and problem 1 re-occurs!
One further piece of info, boots up fine if I remove the power cord overnight.
Any advice, or others who have had this problem would be much appreciated.