After upgrading to Leopard (10.5.1), I've been seeing occasional random 1 pixel horizontal lines across Safari windows (and occasionally in Entourage). They do not go across the whole screen of my 20" iMac, just across the window of the program, and sometimes not even from side to side. I've even seen the line only in the empty part of a scroll bar. This is the only trouble I've seen with my Leopard upgrade so far, and it seems to be a recent development.

I haven't seen anything in these forums about this. Has anyone else experienced it? There's a bit on it in the Apple discussions, but it seems to revolve around dust on video cards, which are inaccessible on an Intel iMac (at least for someone like me, with no expertise in the area.) Thanks in advance for any help or direction.

Rory Cooney

Does sound like a video card issue. not sure what you can do about it.

Issues of this sort are similar to video 'tearing', where when you move a window, "echoes" of the trailing edge of the moved window stay behind and are not overdrawn with what was under them.

I've heard of this problem but in 10.4.11. A combo update might have fixed it, so far anyway. If it doesn't go all the way across it's not the video card. If it was the video card it would not be in only the Safari window, it would also go from edge to edge on the screen. It may be a video driver issue but not a hardware issue.

I'm having the exact same issues. But my lines are in also in FireFox, Adobe Lightroom.
It started after I patched my iMac to 10.5.2 and shortly after som Apple pro application patches. Don't know why I need those. Maybe because of the Aperture 2.0 trial.

I don't think it's an issue with the graphics card since, as someone said, the lines would be across the whole screen and not just in applications. It might be an issue with the drivers, though.

Argh. Starting to hate 10.5.2. System crashes - apparently because of Lightroom metadata in som Image files and my Airport hangs all the time.

Hoping to see a fix soon.

Having the same issue with a MacBook Pro 10.5.1. Took it to the shop and they couldn't find anything. Sometimes my lines have splashes of color... green mostly.

Yeah, I had green lines too. Jagged, ugly green lines.

I reinstalled Leopard few days ago, figuring that the faulty drivers/updates would be removed.
Right after installation when leopard starts for the first time and you get to create your user-account with a picture using iSight, the monitor went completely blank/black. That was a clean install without any updates. So I figured the Graphic Update (which I believe introduced the error) must have updated the Firmware.

After a cold restart, I tried to recreate the error so I could send it of to Apple Service, but the system seemed stabil. No black or green lines and no monitor black-out.

Today I opened some JPEGs in Preview. The files had been in the Lightroom library before re-installed the system. I again had horizontal lines before the monitor again had a black-out in the end. So now I'm back with two possibilties: Lightroom metadata in image-files craches in Apple's applications or a problem with the graphics driver/firmware/Apple graphic software.

Read this forum entry Random Shutdowns: Leopard Graphics Update, so I guess I'm gonna try that out.

Sent it off to service today. Don't want to make this my problem and I don't want to sit and wait for at fix. Now it's Apple's problem.