Been trying to sort out an ongoing intermittent problem on with my G4 flat panel iMac for some time now. I get kernel panics and display problems - the screen starts breaking up into thin horizontal lines at times. I've run the Hardware Test several times (including loop mode overnight) and got an error code only once: disp/13/3 - problem with video ram. Thing is, the problem doesn't seem to show up when I run in Safe Mode, which I've been doing for extensive periods the last while. This leaves me thinking it may be a software problem (I don't know much about this, so correct me if I'm wrong). I tried upgrading from 10.3.9 to Tiger - didn't solve the problem. Would like any input on the possibility that it is a software problem, also on whether an Archive and Install or an Erase and Install might work better than the upgrade I tried. If so, I'm really hoping for some indication that an Archive and Install will have the same potential effect as an Erase and Install, because I'm way too busy right now to deal with an Erase and Install unless I really have to. Any input on this greatly appreciated, thanks in advance.
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hardware or software problem?
- Thread starter dsyroi
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Sounds like it could be a GPU driver problem in which case the Archive & Install may help. It certainly has more chance of helping than the Upgrade had, because the latter won't reinstall the drivers. Good luck. 
I have to second mad_jew. It most likely is a GPU driver, or another driver that is not working properly with the hardware. An archive and install should clear up the mess.
Hi
have to add that the diagnostic disks actually talk directly to the VRAM. There are no drivers involved. unfortunately it does sound like there is a intermittent failure on one of your VRAM chips, this defiantly relates to the fact it happens when it comes out from sleep. This is when the vram is flushed.. but there is no harm in a fresh install. I have seen this before and it usually goes away after the computer warms up or as you said only noticeable when you wake it from sleep.
hope this helps
have to add that the diagnostic disks actually talk directly to the VRAM. There are no drivers involved. unfortunately it does sound like there is a intermittent failure on one of your VRAM chips, this defiantly relates to the fact it happens when it comes out from sleep. This is when the vram is flushed.. but there is no harm in a fresh install. I have seen this before and it usually goes away after the computer warms up or as you said only noticeable when you wake it from sleep.
hope this helps
thanks for the input, one other question
thanks for the replies, I'll try the Archive and Install. One other question: Is the vram a replaceable part, and if so, is it an expensive repair? I'm not keen on throwing too much more money into this machine, but it still does pretty much everything I need it to do (would love a larger screen though).
thanks for the replies, I'll try the Archive and Install. One other question: Is the vram a replaceable part, and if so, is it an expensive repair? I'm not keen on throwing too much more money into this machine, but it still does pretty much everything I need it to do (would love a larger screen though).
Hey
Unfortunatly the VRAM is embedded to the logicboard, So the only way to repair the issue, would be to replace the whole logic board. Depending where you go it should'n't be that much. What is the speed and screen size of your imac i will PM you the part cost.
Unfortunatly the VRAM is embedded to the logicboard, So the only way to repair the issue, would be to replace the whole logic board. Depending where you go it should'n't be that much. What is the speed and screen size of your imac i will PM you the part cost.
thanks for the input, one other question
Matthew:
thanks for taking the time to help out. I have a pretty good idea of the cost of replacing the logic board because I had to do that about a year ago. I think at this point I'll try the Archive and Install and if that is unsuccessful I'll just go ahead with a new iMac. Thanks to the other responders as well.
Matthew:
thanks for taking the time to help out. I have a pretty good idea of the cost of replacing the logic board because I had to do that about a year ago. I think at this point I'll try the Archive and Install and if that is unsuccessful I'll just go ahead with a new iMac. Thanks to the other responders as well.