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popheader · Aug 28, 2004, 09:44 PM

HI I'm curently running an imac grape rev. c with a Powerlogix G4 500 mhz processor with 384 MB ram and 10.3.4. I have the backside cache running at 143 mhz which is second from the bottom as for speed, much higher than that and it will crash my mac. For the past few weeks my imac has been crashing with the black screen that says you need to restart your computer. This usually happens after I've been using my mac anywhere from 30 minutes to 2 hours; I get no warning when the screen goes black- I could be typing something or the computer could be sitting idle then BAM! I've replaced the battery for the clock hoping that might be the problem, but I kind of wonder if it isn't a heat issue? I have a spare analog board but I am waiting to the end to try that, since I hate the process of flashing the rom for the new processor; so I thought I might ask if anyone here might have an idea as to what is causing this. Bad Memory? I hate to put anymore money into this thing if possible. Thanks in advance.

Detrius · Aug 29, 2004, 05:10 PM

It is DEFINITELY not the analog/video board. It's impossible. Possibilities: software, RAM, processor, logic board, hard drive. Anything else is reaching.

sideus · Aug 30, 2004, 02:21 AM

Originally posted by Detrius:
It is DEFINITELY not the analog/video board. It's impossible. Possibilities: software, RAM, processor, logic board, hard drive. Anything else is reaching.

Why is that impossible?

Detrius · Aug 31, 2004, 09:05 PM

Originally posted by sideus:
Why is that impossible?

For the same reason that a bad inverter on a laptop cannot cause a kernel panic; a bad CRT also cannot cause a kernel panic. The Analog/Video board controls the CRT. It can cause a machine not to boot, but it cannot cause a kernel panic.

sideus · Aug 31, 2004, 09:54 PM

Agreed.

Detrius · Sep 1, 2004, 07:00 PM

From the sound of it, you have more than one RAM module. Pull one of them out. See if the problems get better, worse, or don't change. If they get worse, it's likely the module that you left in the machine.

popheader · Sep 5, 2004, 03:27 PM

Thanks for the suggestions, I ran Diskwarrior and that really speeded things up, but I still am having the KP's. Sometimes I get the black screen of death which says I need to restart and other times I get a frozen screen just locks up. Then I have to restart. Well I pulled the top 256mb module from my mac and now am running on the 128mb module only. I will see how this lasts. Can anyone tell me if I can run my mac with ram in the top slot only and not using the lower slot, since I don't have another module that will fit there. I will keep this post updated incase anyone might be having similar problems. P.S. I need to make a correction to my original post regarding having another analog board, what I meant to say was that I had another logic board a 233 rev. a I believe which I intend to try next incase this problem isn't solved by the ram issue.

popheader · Sep 12, 2004, 12:33 PM

Hi Thanks to everyone who helped me out. I tracked down the problem to a corrupted driver which runs the speed of the backside cache for the Powerlogix G4 chip. I ended up uninstalling and reinstalling the software for the cache enabler and wala I'm back to no more problems, I feel as if I can keep this imac going for another year or two no problem!