Corrupted video card? Driver?

[hayduke]

I have a powerbook 1.67GHz machine and the video card or driver (...or something!) is on the fritz. The "internal" screen frequently gets totally scrambled, but if I am hooked up to an external monitor in mirror *or* extended desktop mode the external screen appears completely normal. The problem is intermittent and usually goes away after ~1-10 minutes, but may reappear after after a few tens of minutes or hours. It seems to happen most when I start using the laptop in the morning, so perhaps it is related to using the video card when it is "cold." Also, a screen capture (command+shift+3) of the internal screen appears totally normal (probably not surprising). I feel like this problem started after I installed flip4mac, but have since uninstalled every remnant (...I think) and updated the OS to 10.4.7, but still the problem persists. I ran Apple's hardware test (boot from the service CD, ran the test overnight), but the test only returned normal results and no problems.

Any ideas? I'm still under AppleCare so I can send it back, but because it is intermittent I'm afraid it will just get sent back unrepaired. Or, if it is a software problem they might charge me to fix it. Thoughts. I've attached a digital photo of the scrambled screen. Looks bad, eh?

 

[michaeldmartin]

They fix that kind of problem, my guess is a loose display cable, so when you move it, it gets jiggled around, try it on a stable surface w/ external keyboard for 30 mins and see if it happens again.

 

[hayduke]

I thought about it being a loose cable. It seems a little strange that the problem mostly goes away once things warm up, but this seems like an odd software problem too. I guess I just wanted to hear if anyone had ever heard of this kind of problem having a software origin or if I have to back-up and ship out the PB for a few days.

 

[funkychunkz]

If there were such thing as a software goof-up that bad, I don't think it could be working. Itr's the hardware.

 

[Erasmus]

That reminds me of one of our laptops... Black G3 233Mhz Powerbooks. When it happens, it occurred from start however. Moving the mouse would make some pretty wierd things happen. Almost as if some of the wires in the connector were crossed... making graphics lines appear where they shouldn't...
Anyway, any chance you could do a full system format and install? Just in case, and to check that it isn't hardware.
I seem to remember that ours just stopped doing this, so you could be lucky yet!

I hope you find the solution.

 

[hayduke]

So, after having looked at a PB disassembly guide and discovering where the video card is I can press on the P,{/[, and }/] keys and usually get the problem to go away. So I'm pretty sure its a *software* problem...not!

I guess this little baby will get packed up soon.

 

[Lord Blackadder]

If it works fine on an external display it is probably a problem with the PowerBook's built-in screen, but not the GPU. A GPU problem could be caught by screenshots, while a display problem won't.

Send it back to Apple or take it to an Apple Store for repair...

 

[Fleetwood Mac]

If it works fine on an external display it is probably a problem with the PowerBook's built-in screen, but not the GPU. A GPU problem could be caught by screenshots, while a display problem won't.

Send it back to Apple or take it to an Apple Stor for repair...

I'd take that/send that picture along too-just incanse the problem can't be replicated.

 

[esternullo]

i have a the same problem with a Powerbook G4 Ti, and it appears on the external monitor as well.

what is the problem?

 

[gretafour]

I know I'm resurrecting an old topic. My powerbook (quite out of warranty) is just now exhibiting the same symptoms. The distortion itself is always flickering horizontal lines, sort of like static on a TV. Putting pressure near the trackpad and above the keyboard can make it better. Does not seem heat-related. The distortion does not show up in screenshots, and is not changed by adjusting the display.

I haven't be able to hook it up to an external display yet, but the fact that my screenshots are clean seems to rule out the video card. Right? I took this with my camera:

 

[gretafour]

Correlations

Well, I discovered that maxing out the CPU (such as with iTunes Visualizer) tends to remedy the problem, but only so long as the CPU is at or near 100% usage. When I stop the visualizer, the distortion returns.

I also just noticed a correlation between sleep and the distortion: if I put the computer to sleep and then wake it, the problem is gone, at least until I reboot again. What to make of this? Ideas anyone?

 

[BlueRevolution]

I don't think there's much we can do. I'd suggest searching Apple's support docs. If that doesn't work, you'll have to take it in to the shop. From the problem, I suspect you may need a new logic board, which I'm afraid will cost more than your computer is worth.