PMG5 crashes while running Thermal Calibration

Discussion in 'PowerPC Macs' started by iamMacPerson, Aug 10, 2019.

  1. iamMacPerson macrumors 68030

    iamMacPerson

    Joined:
    Jun 12, 2011
    Location:
    AZ/10.0.1.1
    #1
    So I just picked up a free OG dual 2GHz G5 today and have been working on it most of the day. I have come across an issue though. Whenever I load an app or anything, the system revs the fans like crazy then they settle back down. Having had this issue before, I repasted the CPUs and went to run the Thermal Calibration test from ASD 2.5.8.

    Everything is fine until about 15 mins in when it crashes. And I don’t mean it locks up; The computer completely hard powers off. It comes right back on and I do not have this issue while booted into Mac OS X but what could be causing this crash? It also has not made a bit of difference as the fans continue to rev. I’m thinking it may have a problem writing the new thermal calibration into NVRAM or wherever it’s stored.
     
  2. FrancoisC macrumors 6502a

    FrancoisC

    Joined:
    Jan 27, 2009
    Location:
    Montreal, Qc
    #2
    Try to check the voltage of the NVRAM battery maybe? If that's the source of your problem it's an easy fix ;) Otherwise maybe faulty PSU that only trips when system is at 100% load, which I THINK (really not sure here) that is what happens during thermal calibration.
     
  3. iamMacPerson thread starter macrumors 68030

    iamMacPerson

    Joined:
    Jun 12, 2011
    Location:
    AZ/10.0.1.1
    #3
    Already replaced the battery sadly. Maybe I’ll try hitting it with a 100% load in the OS and see what happens.
    --- Post Merged, Aug 10, 2019 ---
    Hitting it at 100% load, all had been fine for about 5 mins. Here’s something interesting though: the CPU0/CPUA’s fans are running much faster than CPU1/CPUB’s. Plus the air from CPU1 is much hotter (as expected). Could it be an issue with CPU0? That’s the chip that fails calibration.
     
  4. RhianB macrumors 6502a

    RhianB

    Joined:
    Sep 3, 2016
    Location:
    505 USA
    #4
    Run just one cpu - the cpu in question & see if it works. If it’s dead, you’ll know pretty quick.
     

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3 August 10, 2019