3 Replies Latest reply: Mar 23, 2011 12:03 PM by K Shaffer
Dave Troup Level 1 Level 1 (105 points)
I'm trying to remotely help my mom to solve a big problem with her iMac G4 (2007 vintage.) It's running Mac OS 10.5.8. Everything was fine until a couple of weeks ago when it started refusing to boot. It starts to boot, you get the Apple and then it continues on to the blue screen, and never progresses from there.

It WILL safe boot, and I've tried all the things I can think of... disabled login items, reset PRAM, used Disk Utility to check the HDD and repair permissions. But it won't boot in normal (non-safe) mode.

So I decided the only solution would be to archive and install Leopard again. I figured the hardware was mostly likely okay, since it would safe boot. She couldn't find her Leopard install disks so I sent her mine.

But the system won't successfully start up from the install DVD. It does read from the DVD and starts the boot process, but again it hangs at the blue screen and does not continue beyond that.

I am not sure what to try next... I suppose it's possible that there some bad RAM or something which isn't accessed during the more limited safe boot but is used during a regular boot and causes the hang. It seems like the HDD is probably okay since it consistently safe boots without a problem. What else can I try?

Any suggestions are greatly appreciated!

Intel 3.2 Ghz i3 iMac, Mac OS X (10.6.6), MacBook Pro 13", iPhone 4, iPad 64 3G
  • K Shaffer Level 6 Level 6 (10,625 points)
    If both computers involved shipped with 10.5 Leopard, the disc you sent may
    not be compatible; since they likely are different build models. Was the DVD
    you sent a 'gray label' software install-restore disc?

    A 2007 iMac would have been an Intel-based Mac; not a G4 or G5 (PPC.)
    +{My avatar is an image of an iMac G4 with 16:9 17-in or 20-in LCD panel.}+

    The hardware test on the ailing computer's original software restore-install disc
    set would be helpful, in that the Apple Hardware Test can help with diagnostics.

    A different disc for another model, won't do that; nor would it boot the computer.
    So the usefulness of the disc you sent may be nominal if Disk Utility on it can't
    work, and if the DVD you sent, won't boot the other computer, or causes harm.

    Sometimes, a startup in SafeBoot mode, then run Disk Utility's verify disk, and
    run 'repair disk permissions' may help; since some checks & repairs are done
    on startup into SafeBoot. (shift key held down through startup; then login.)

    • Resolve Start-up issues and perform disk maintenance with Disk Utility, and fsck
    +(a command-line utility)+ ...
    http://support.apple.com/kb/TS1417

    Anyway, the computer probably isn't a PowerPC G4/G5, if it's from 2007.
    A relatively new computer which may have shipped with Leopard 10.5.x
    invites a call to Apple (main number) to get a replacement install DVD set.

    Good luck & happy computing!
  • Dave Troup Level 1 Level 1 (105 points)
    Thanks for your reply. I might be wrong about 2007, maybe it was 2006. I do know that this was the last iMac series to carry a PowerPC CPU. When my mom bought the computer, the first Intel versions had just come out, but somehow she bought the older one, I think they were trying to get rid of the old stock.

    You're right that it wasn't shipped with 10.5 Leopard; but it's been upgraded over the years. The installation disk she is using is a retail 10.5 DVD which should not be specific to a particular model. She has the original install disk for the machine, but it's an earlier OS version (10.4? 10.3? don't remember) and I don't think we want to install that on top of 10.5.

    But there's updated information since my original post... somehow the machine finally booted from the (retail) 10.5 install DVD and I was able to walk her through doing an archive and install. This completed successfully. However, when the iMac rebooted at the end of the installation process, once again it hung at the blue screen part way through the boot process.

    I have tried repairing disk permissions while in SafeBoot mode, but it didn't help with this problem.

    I'll try to walk her through running the hardware test on the original software restore-install disk.
  • K Shaffer Level 6 Level 6 (10,625 points)
    The test as run from the original install-restore disc #1 should be accessible
    when booted per instructions on the label. Usually, there's the method on how
    to use the Installer (C key on boot) and also the other is there, on how to use
    the same DVD to boot the Apple Hardware Test (perhaps Opt key.)

    With an older computer, there is the chance the hard disk drive may be fading;
    due to use and age factors. However, one could still (maybe) find information
    on what else may be going on, IF the error and crash logs in the Console utility
    could be accessed, then read through, by someone with technical knowledge.

    The Console logs may be accessed if the computer can be started in SafeBoot.
    And there are several, in there; some would not apply. Also, they're rather cryptic.

    Sometimes, a section of a hard disk drive where the boot information is stored
    could be damaged; or the Directory may be corrupted, so a third-party disk
    utility on its own DVD or bootable volume can be helpful to correct that aspect.
    Or to totally erase, zero, partition map and reformat the hard disk drive may do
    to attempt to restore function of the computer to normal; while wiping user content.

    A backup of content could be made; even a clone copy to an external, then that
    could be transferred (via another clone, using Carbon Copy Cloner, etc) and if
    the computer were wiped, that bootable clone could be moved back. Or, should
    the internal drive be bad, the content of the computer can be put into a new HDD.

    {The 'pizza box' iMac with the G5 PPC processor, had a few known issues in
    certain models, some due to heat and other component failures; so the hard-
    ware test may be helpful. So would an inspection of the power & logic circuits.}

    Anyway, sounds like 10x the trouble at a distance, helping someone figure out how.
    Good luck & happy computing!