Weird dotted lines and freez-ups

Question

Hello everyone,
I've got QuickSilver PM dual G4 1GHz, a couple of days ago it started acting really weird.
After wake-up and sometimes on fresh reboot, some kind of dotted lines would appear at random places on the screen, interface elements would get distorted and after few minutes beachball would appear as well, rendering system unusable. Mouse pointer would still be active/movable, but nothing will be clickable. If I leave it like that long enough, Kernel Panic message would appear eventually.
I tried to re-install system, clean install, reset PRAM, wipe disk clean and install. All updates are installed as well. Running 10.4.5 right now, as I suspected 10.4.6 update of causing this, but that wasn't the case.
Apple hardware tests reports "passed" on all counts.
I even tried with new user, thinking that my user data could be corrupt. But nothing helps.
I haven't installed any new hardware recently, so I don't think that's the problem.
Anyone else having similar problems?
Or have some new ideas what could be causing this?
And ofcourse, maybe know, how to fix it?
Best regards
Nihad E.
QuickSilver PowerMac Dual G4 1GHz   Mac OS X (10.4.6)  

Answer 1

Nihad:
Sorry to hear you had to buy a new Mac, prior to getting your older Mac fixed. There are a couple of simple things you could try, maybe you already did.
A co-worker had a problem with a G4 that would give weird screen fonts and colors. Despite having the IT dept come look at it, nothing was solved. Turned out to be the cable connector from the monitor to the back of the Mac was either a bit loose (not noticeably) or had some dust in it. Unplugging that connector, blowing it off and reconnecting it solved the problem.
Another thing you could look at is the PRAM battery. I know that in the Beige G3's, this battery can cause a host range of wierd symptoms. I have a friend who originally had a pre-Beige Mac (PM7300 or similar) that wouldn't boot, assumed it was dead and bought a Beige G3. Turns out that the PRAM battery was dead in the PM7300. My Beige G3 would randomly shut down and refuse to boot when it's PRAM battery went dead.
The battery is cheap (like $5-10) and should be relatively easy to replace. I wasn't able to find a logic board layout for the Quicksilver, but most of the Macs seem to have the battery located near the PCI/AGP slots. Here's a pic of the battery from OWC:
PRAM battery
Once you've replaced the battery, if your G4 has any sort of cuda or PMU button (a button located on the logic board that does a complete reset), depress this button for about 10-15 seconds and try rebooting the machine.
Upon doing those two things (I'd try them first), it sometimes helps to get inside the Mac and reseat all the RAM, cards, etc (I wouldn't mess with the cpu, unless you've recently taken it out or upgraded it). Look for dust, bent pins, anything abnormal. Put everything back in order, do a reset (logic board button) and reboot.
Good luck!
A.