power mac g5 RAM problems

[clsmooth1982]

been lurking here for over a year and finally decided to register. and what a time to register, indeed. ok, here's the situation that i'm in...

girlfriend's computer (power mac g5...older model...purchased around may of '04...has 4 RAM slots) gives out last night. she was using safari and internet explorer and the applications would quit on her. all of a sudden, the desktop would dissapear, then re-appear and then a weird kernal message on the desktop shows up and locks up her entire computer. i unfortunately don't know what the error message was exactly, but i rebooted the computer and it would not get past the grey start-up screen. i then rebooted again, inserted the mac os x install dvd and went into apple hardware test. it ran the hardware test and everything came out ok except for the ram. it gave me this message:

post/0/2048 DIMM0/J11

doing some google searches told me that the RAM in one of the DIMM slots, DIMM0 to be exact, was no good. i opened up the g5, removed all the ram and trial and error'd installing the RAM until the apple hardware test showed me that there were no errors regarding the installed RAM. i am at that point now where i have ran the apple hardware test, both quick and through tests, and everything comes out fine. we're talking logic board, hard drive, memory, video card...the whole nine yards. i reboot the computer and now it still won't get past the grey screen. what do i do? how do i get past the damn screen?! applecare has long expired, so i don't feel like dropping $200 on a service call request. can someone PLEASE help me out here?! i'd really appreciate it!

 

[CanadaRAM]

The hardware test was pretty specific that DIMM0 was the problem RAM. Unfortunately it sounds like you have moved the modules around so you no longer know which was the original DIMM0 ? (there should be a legend on the motherboard that says what the slots are numbered)

Anyway: It is time to get a new, known-good pair of RAM modules and put them in. Then test.
Alternatively, test your machine with the modules 2 at a time until you isolate the module that makes it fail.

The problem is that Apple Hardware Test will not catch all errors, all the time. So you put the bad DIMM back in, lucked out on one AHT, but now it is flaking out again.

Was the RAM Apple stock, or is it third-party? If it is from a TP like Kingston, Crucial, OWC or DMS you you might get it replaced under warranty.

 

[clsmooth1982]

The hardware test was pretty specific that DIMM0 was the problem RAM. Unfortunately it sounds like you have moved the modules around so you no longer know which was the original DIMM0 ? (there should be a legend on the motherboard that says what the slots are numbered)

Anyway: It is time to get a new, known-good pair of RAM modules and put them in. Then test.

Was the RAM Apple stock, or is it third-party? If it is from a TP like Kingston, Crucial, OWC or DMS you you might get it replaced under warranty.

i ran apple hardware test after i moved the RAM around and it said that the ones i put in there are alright. when i ran the hardware test before, the bad ram slot was in red. there are no red RAM slots in the apple hardware test now when i run it. (sorry, i should've mentioned that earlier).

 

[CanadaRAM]

Well, RAM doesn't fix itself (unless it was a simple matter of needing reseating in the socket.) But you're still crashing on boot, correct? So something is still wrong regardless of the fact that it passed AHT once.

Make sure you leave it long enough on the gray screen. sometimes it takes 10 - 15 minutes - especially if Startup Disk has been set to Network Startup or a non-connected volume.

Does it boot from the OSX CD/DVD at all? (Restart, hold the "c" key down)

If it boots reliably from the CD but never from the hard drive, then you have a hard drive or OS problem. Keep in mind that bad RAM can corrupt the contents of a hard drive too, so you may have both a hardware problem and a secondary symptom (b0rked OS on hard drive).

If it fails to boot from the CD, then despite what you would prefer to believe, you still have a hardware problem, likely RAM

 

[Kosh66]

Actually to me it sounds like it may now be a software or bad HD problem. You mention that you ran the hardware test, which means the PM G5 booted from the System Disk. Yet, the PM G5 doesn't boot (fully) from the HD. Did you try repairing the HD from the System Disk? Did you try repairing permissions from the System Disk?

 

[clsmooth1982]

Actually to me it sounds like it may now be a software or bad HD problem. You mention that you ran the hardware test, which means the PM G5 booted from the System Disk. Yet, the PM G5 doesn't boot (fully) from the HD. Did you try repairing the HD from the System Disk? Did you try repairing permissions from the System Disk?

i know this sounds like a newbie question, but if i reinstall the OS, do i lose everything on the hard drive? or do the non-OS related documents (word documents, iCal, etc.) stay while the OS just re-installs the OS files?

 

[CanadaRAM]

i know this sounds like a newbie question, but if i reinstall the OS, do i lose everything on the hard drive? or do the non-OS related documents (word documents, iCal, etc.) stay while the OS just re-installs the OS files?

FIRST do the Disk Repair from the Disk Utility found in the Utilities menubar menu once you boot from the Installer CD, like Kosh says.

Then if it gives the drive a clean bill of health, you can proceed with installing an OS using the "Archive and Install" option. This will preserve your user account and data and programs, and only install the OS.

 

[clsmooth1982]

FIRST do the Disk Repair from the Disk Utility found in the Utilities menubar menu once you boot from the Installer CD, like Kosh says.

Then if it gives the drive a clean bill of health, you can proceed with installing an OS using the "Archive and Install" option. This will preserve your user account and data and programs, and only install the OS.

i did disk repair and then repair disk permissions, but when i did repair disk permissions, it went to about 85% (guesstimating by looking at the progress bar) and then it gave me an error message asking me if i wanted to quit disk permissions. i'm leaning towards installing the OS again and seeing if that helps. i'm making an image copy of the main drive with the OS on it to an external hard drive just to make sure i don't lose any of her important files.

i really appreciate everyone's help with this so far.

 

[FireArse]

Startup

Do you get the spinning gear at startup - or just clear grey screen?

I would concur that it could be a HDD or startup file issue. Try a 'safe' startup by:

Using Safe Boot

Ensure the computer is completely shut down.

Press the power button.

Immediately after you hear the startup tone, press and hold the Shift key. (preferably with wired keyboard)

Release the Shift key when you see the gray Apple and the indeterminate progress indicator (spinning gear).

If it starts up - RAM isn't your issue

F

 

[scottlinux]

Or boot up in single user mode, via holding Apple key + S.

See if it boots up fine then.

 

[knockknock]

Or start up pressing X <-it's safe mode.
-So many keyboard shortcuts that Apple should include them printed along the restore discs.