6 Replies Latest reply: May 14, 2009 3:11 PM by Lyssa
vjejjala Level 1 Level 1 (0 points)
I tried upgrading the OS to 10.5.7 today on a two and a half year old MacBook Pro. On restart and install, the upgrade failed. Subsequent attempts at restart lead to an error message that begins:
panic(cpu 0 caller 0x001AC125): ~Version mis-match between Kernel and CPU PM~@/SourceCache/xnu/xnu-1228.12.14/osfmk/i386/pmCPU.c:638
Of course, I have no idea what this or the subsequent lines mean.

I have the Leopard OS X install DVD and a Time Machine backup on an external drive. Overlaid on the above error message, I get the "You need to restart your computer...." prompt irrespective of whether the install DVD is in the drive.

I would be grateful for suggestions on what I should do.

Can I reinstall Leopard from the DVD and try upgrading to the latest version of 10.5 afterwards? How would I do this?

Copious thanks and best wishes,


MacBook Pro, Mac OS X (10.5.7)
  • Allan Eckert Level 8 Level 8 (48,570 points)
    Hi vjeijala;

    You have had a kernel panic. Generally these are caused by hardware most frequently bad RAM. I would suggest that you run AHT to test out your hardware first.

  • Richard Prescott Level 1 Level 1 (90 points)
    I think the larger question is whether or not you can still boot to the installer DVD.
    - Leave the DVD in the drive, restart the machine and hold the D key down to start to the AHT part.
    - Select the extended test and before you run it click on the Hardware tab to see if it sees all the RAM you have installed. Any RAM flagged as bad will be written in red text.
    - If you see no red flagged RAM then go back to the Test tab and run the test.
    Just remember, you said you have a Time Machine backup. I found it easier to restore from backup (took about 1.5 to 1.75 hours on my Mac Pro restoring about 175 GB).
    That is why we have Time Machine.
    Select the last backup before the update to 10.5.7.
  • vjejjala Level 1 Level 1 (0 points)
    How do I run the AHT? Almost immediately after I hit restart I encounter the kernel panic that I described.


  • vjejjala Level 1 Level 1 (0 points)
    Holding the D key down with the install DVD leads to the same panic error message that I have described. Is there a way to force the machine to boot from the Time Machine backup or have the machine look at the backup and restore things to how they were yesterday before proceeding to do anything else?


  • owl5126 Level 1 Level 1 (0 points)

    Message was edited by: owl5126
  • Lyssa Level 6 Level 6 (17,745 points)
    Restoring from a TM backup requires booting from the install disc.

    Try removing & reseating the RAM in the machine, as well as running on first one module, then the other and see if that solves things.

    See this article for how to remove and reseat RAM: