Bizarre Horizontal Pixel Lines Through Screen (Application Windows and Desktop).

crjeong

macrumors member
Original poster
Aug 29, 2006
77
0
Sydney, Australia
I've been getting these weird horizontal lines through my apps and occasionally my desktop.

See attached image.

I thought it might have been a graphics card problem, but these lines move with the apps even in expose mode.

Any ideas? Its driving me nuts. I had this problem before while on 10.4 Tiger and now again on 10.5 Leopard (fresh install on new hard drive).

I called Apple Australia and they didn't really offer me a solution.

What could be causing this?
 

Attachments

absolution

macrumors member
Aug 30, 2007
40
0
If the problem has persisted through an OS install, it's probably not a software issue. How are you connecting to your monitor? DVI or VGA? What is the run distance? Going by the image it looks like a bad DVI connection. This could mean either the run distance is too long (i.e. over the 15m recommended distance for DVI-D) and the signal is degrading, or the cable doesn't have enough shielding and it's picking up interference along the way. I would try reseating the connections (back of computer and back of monitor) and see if that helps. If it doesn't, try a shorter cable. If that works, you need a new cable, one with more shielding to protect the signal for your run distance. Monoprice makes great, beefy DVI-D cables for long runs. Cheaper than everyone else too. Good luck! :)
 

product26

macrumors 6502a
May 30, 2005
774
10
try a different monitor... try a dvi to vga adapter with a vga monitor.

if that doesn't fix it... move on to the video card.
 

KevinPlusPlus

macrumors member
Sep 16, 2007
92
0
USA
There are some very long threads about this ATI card problem over at the Apple user forums. The typical solution is to get your video card replaced by Apple, apparently these artifacts are the result of overheating of some of the earlier revisions of the ATI cards. (That's the general consensus, anyway.)
 

ShadowXOR

macrumors regular
Jun 3, 2008
150
0
Washington
I'm having this exact same problem with an NVIDIA card, and I just got my iMac back they replaced the video card, logic board, display...and that's the second time they've had to do it, help?
 

goMac

macrumors 604
Apr 15, 2004
7,064
1,088
I thought it might have been a graphics card problem, but these lines move with the apps even in expose mode.
Doesn't matter. The windows could be corrupt in VRAM, meaning the corruption would scale and move with them.

Edit: %$%$% fooled by a dead thread.
 

goMac

macrumors 604
Apr 15, 2004
7,064
1,088
Probably has an iMac with an 8800 card. Those things are known to be defective, and will always die, not matter how many times replaced.
 
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