Mac Pro Shutting down/Sleeping automattically and randomly

[Metalshopteach]

I have a MAc Pro, Bought in January 09, pretty much stock except for an exta 500 gb drive and the Nvidia video card.

I have a strange problem, I will be using the computer and it will just shut down. Ie my LCD monitor shows the "RBG MODE" screen which it shows during a reboot or if turned on when computers off. My Intelli mouse explorer laser mouse turns off but if I click the laser turns on and off with each click and the power light on the tower is lit but nothing turns the machine off/on unless I hold it down till it reboots.

This has been happening since about the beginning of July, happened last week again every 10 minutes or so it would do this. Saw a post that said it's cause its too hot and its shutting down for safety, I have Istat and the temps at that time was 35 degrees celcius ambient and the processors when watching a dvd or somthing was around 40 degrees, I installed smc fan control and ramped up my fans and with them runing 1500 rpms the temperatures have been steady at around 32 ambient and 35-37 for the vaious sensors. Today the heat wave is over and istat says the ambient is 26, processors and drives are still 35-37 and it rebooted again.... is my machine running hot or is it somthing else.. I am at a loss. It is a Stat holiday here so I cant call my local repair place. Running OSX 10.5.7 any other info is available if needed.

Mac Specs


Model Name: Mac Pro
Model Identifier: MacPro3,1
Processor Name: Quad-Core Intel Xeon
Processor Speed: 2.8 GHz
Number Of Processors: 2
Total Number Of Cores: 8
L2 Cache (per processor): 12 MB
Memory: 2 GB
Bus Speed: 1.6 GHz
Boot ROM Version: MP31.006C.B05
SMC Version (system): 1.25f4

 

[geoffreak]

Seems to me that your power might be failing if it is just shutting off.

 

[j2048b]

either power supply or your logic board? call apple as it should be under warranty!

 

[Metalshopteach]

I will call them tomorrow. It is def. under warrenty, I paid for the extended.

 

[Metalshopteach]

Sooooooo I just got a call from the tech guy, said he found nothing wrong, hardware or software...... so what should be my next step, take it back use it till somthing completly fails on it, reinstall OSX?

 

[killerrobot]

If he tested all the hardware and found that it was okay, then I'd assume there was probably some glitch with the SMC. He probably reset that, but I'd reset it as well if I were you.
http://support.apple.com/kb/HT1806
I'd also copy the crash.log file from the Console in the Utilites folder into a text file every time a crash occurs if the problem continues as proof that it is happening to show the tech.
A side question. Are you plugged directly into a wall outlet or into a power strip?

 

[Metalshopteach]

Havent done that myself, I will ask him to do so before I pick it up, and will copy the log, I am plugged into a surge bar/strip then the wall

 

[Metalshopteach]

They did another test and found the hard drive to be faulty, I'll have a new one in by friday