macPro 8 core shuts down randomly

[Dmartin714]

hello all,

So I currently am running a 2008 MacPro with Snow Leopards as my osx. Recently it started shutting down, not restarting, just turning off. I took it into the apple store and they said it was probably my power supply. Well, $204.00 new power supply, same problem.

I had a Digidesign audio interface plugged in, and a seagate external hd, after reinstalling the OS, unplugging these devices I still get the randome shut downs. Which leads me to believe there IS something up with the computer. All SMC and whatever else has been reset. Ian currently running 10GB of ram, but the computer only recognizes 6gb. Took out the 4gb that were acting up, and still the shut downs happen.

They aren't consistent at all either. The computer can run for 3 days just fine, then on day four it will crash over and over again.

Any suggestions? Graphics card? Logic board?

Thanks!

 

[Nethfel]

If it's hard powering off, my first thought would be that it's overheating. I'd probably check/clean the system of dust and maybe start running something like iStat to keep an eye on your temps. There is always a possibility that your logic board is failing or that you got really unlucky and got a second power supply that was actually bad as well. Do you have any additional internal hardware (aftermarket video cards, other adapter cards, etc.)? Your '08 Mac should have come with a DVD disc that I do believe has AHT on it, if you can find the disc and it does have the Apple Hardware Test, I'd probably try a diagnostic. I'd also do the other standard battery of troubleshooting (check the HD, verify permissions, etc.)

If it's a thermal issue I'd first make sure the comp is clean (really clean, heat sinks blown out, dust blown out from the fans, confirm fans are spinning, etc.) and monitor it really closely.