View Full Version : iMac G5 video problem

03-09-2008, 03:54 AM
I am running Leopard.2 on a G5 Power Mac 1.8 GHZ processor; with 2 512 MB memory chips both the same (manufacturer is stated unknown so is part no. and serial no. on system profiler)status listed as OK; 80 GHZ HD, 37 GHz unused, S.MA.R.T. status: Verified; Graphics on a GeForce FX 5200 64 MB. Did the Graphics Update 1.0
The problem is it freezes up and force quit doesn't seem to work at these occurences. The spinning pizza is the only thing going and nothing will remedy it but a force shut-down via power button.
I was getting a little pixelated display on everything from log-in window, desktop, and application windows.
On some start-ups I would get a triple imaged display and it would shimmer. After 2 to 3 reboots it would clear up. This is after a freeze up of the log-in window.
The display was repaired on a warranty recall a year ago. Are there any similar events out there regarding the same machines w or w/o Leopard.
Thank you in advance.

03-09-2008, 08:21 AM

You are in India? That's the only Cochin I know of. My wife, son, and his wife were in India recently, Pune to be exact, for a followup traditional Indian wedding organized by her parents after their original wedding here in California. But I digress...

Do you have a backup hard drive for your internal hard drive? If so I would think FW400. You have 2 shared FW400 ports. I'm going to ignore the USB2 ports, because they are dog slow.

MacFixIt says:
"Mac OS X 10.5.2 Special Report: Determining whether problems are caused by Mac OS X 10.5.2 or Leopard Graphics update

A number of issues covered in this report -- particularly those regarding wake-from-sleep, display resolutions missing and DVD Player freezes -- may be caused by the Leopard Graphics Update 1.0 rather than Mac OS X 10.5.2. Since the two updates were released and applied by users simultaneously, there is some difficulty in deciphering the culpable software release.

See our tutorial on reinstalling the system, then update to Mac OS X 10.5.2 (but ignore the graphics update). If the problem persists, Mac OS X 10.5.2 is the cause of your problem. If it's gone, the Leopard Graphics update was the cause of your problem."

Without a backup hard drive, that is a pretty severe way to determine the problem. You have repaired disk permissions, and either verified or repaired the disk in Leopard Disk Utility? Do you have any other utilities such as DiskWarrior 4? If you have the DW4 CD, you can boot to that and ONLY repair the directory in Leopard. Do NOT use any of the other DW4 utilities.

This is a start anyway. Others may have a better solution. k

03-09-2008, 06:27 PM
I am in Cochin Sask. and yes there is an external HD connected via Firewire, its a WD 500 Gig with max 400 Mb/ sec.; there is 360 GB available.
I blamed the graphics update because thats when it started acting up. I have repaired permissions and booted up from install DVD to verify and repair HD with no notifications of trouble. I had updated to 5.2 earlier in time before graphics. There were no problems then so I will reinstall to 10.5.2 and no graphics.
Any suggestions on reinstall will help because I am not a pro at this yet.
Thank you so much kaye and I will post final results as usual.

03-10-2008, 08:02 AM
A new day. Actually I tried something last night because it seems the only other alternative is to go back to 10.5.1 on your internal drive and that is not easy and still retain your settings, permissions, and software.

First, I backed up the drive/volume I was going to try this on to another drive. Second, I downloaded the Leopard Graphics Update 1.0 here http://www.apple.com/support/downloads/leopardgraphicsupdate10.html
I was hopeful that there might be an uninstaller but unfortunately no such luck, Apple in their infinite wisdom. Now in your case, your backup drive must have 10.5.2, but I presume without the Graphics Update. This is the drive you want to download the Graphics Update dmg package to. The dmg file should be on the desktop of your backup drive.

Double click the dmg file and a window will open with the package file. Double click the package file. Follow the steps in the installation until you progress to Installation Type (you can see your progress on the left side). At Installation Type, you will see a buttton - Change Install Location... which you should click to be able to select your primary internal boot drive for the install of the Graphics Update again.

What we are trying to do is reinstall in case the original install is corrupted plus the reinstall will update several boot caches as it attempts to Restart. Here is where it got flaky for me. It did Restart but I waited for 20 minutes looking at the white screen with Apple logo and gear turning, grinding away. In my case I was restarting to the drive I was reapplying the update to. In your case you are restarting to your backup drive. I waited the 20 minutes hopeful that the boot caches had been updated. It's a pretty big download, 48.9MB, so there must be a lot to alter.

The installer obviously does not expect a reinstallation of the Graphics Update. In my case, I had to do a hard shutdown, press and hold the startup button until the computer shuts down. I don't know if you will have to do a hard shutdown. For me, I waited a minute before starting up again. Startup to the drive altered was fine. You will be rebooting or restarting to your backup drive and will have to try rebooting to the altered internal drive via System Preferences, Startup Disk.

That's all I can offer at this point. Let us know. k

03-31-2008, 08:02 PM
Thanks for all the advice kaye but my logic board is toast, $700 ding. So my alternative is to be Mac deprived till I can afford a new computer. I will take it back to Edmonton on my next trip for a 2nd opinion. I got Macs at work so there wont be a complete withdrawal.

03-31-2008, 08:09 PM
forgot to mention when I reinstalled 10.5 from install disc it froze and the display was all gibbled up like a bunch of lines of different colors jagged across screen. Thats when it got taken to Saskatoon repair shop( it is my usual repair shop and my workplace uses it). There suggestion was don't spend money repairing it.

03-31-2008, 08:17 PM
G5's have a capacitor problem also. Open the back and examine the capacitors (the little cans on the motherboard) IF any look swelled or have grease leaking from the top then these are bad. Apple has a recall on this and should fix it for free. They have done so for my mother's G5 iMac twice now.