Bad motherboard, right?

I don't know the answer to your question, but I have a 6 year old PB 1GHz Ti
and it began to exhibit the same intermittent display distortion a month or so
ago. The computer functions well otherwise. As it is nearing it's useful life for
my purposes, I just brought a unibody MBP. I wasn't about to spend a penny on
any repairs for the old girl and not knowing what the problem was, I didn't
want to wait until it died completely before preparing my substitute.
But, as I say it's an intermittent problem and I can see no obvious trigger.

Have you tried running the extended version of the Apple Hardware test? If you get an error code indicating the graphics chip, that would confirm the diagnosis. But that's what it looks like to me.

Good luck!

I agree. Looks like the logic board has gone into French Impressionist mode, which is fun to look at but not to use.

Hi, UM. IF the logic board is fine, then either the problem resides somewhere downstream from it (in the video cable or the LCD panel), or it's a software problem. I have no experience with Apple Remote Desktop, but I surmise that if the same anomalies appear on a remote computer as on the Powerbook's built-in display, that indicates the same thing it would indicate if you were seeing those anomalies on a second display connected directly to the PB. Connecting a second display directly to the PB would provide a direct test whose results I could interpret more confidently: if a second display shows the same problem when used in mirrored mode, neither the built-in video cable nor the built-in LCD panel is at fault, and the problem must be in the logic board or in software. Starting the machine up from another volume (one that is known not to be corrupt in the sme way as the intenal drive may be) would then tell the tale: if the anomalies persist on both monitors when the PB is started up from a known-good bootable volume, there's a hardware problem, and a problem that causes this kind of video disturbances could only be on the logic board.

It sounds like this might happen when the board warms up. I'm wondering if you might actually have a BGA failure--i.e. the chip itself may test out OK, but the ball grid array which solders it to the logic board may be failing. Just a guess on my part. It's hard to believe that a graphics chip with this much distortion wouldn't produce an error code.

Do you get the same distortion when booted from a disc?