I have a Mac Dual 2GHz G5 purchased in 10/03. I just bought a new Apple 30 HD Cinema Display and after a lot of research splurged on the ATI Radeon X800 XT graphics card to power it. I loaded the software for both and installed both on Thursday evening (despite the card coming with instructions for a different card) and they worked fine. On Monday morning, (bringing the screen out of sleep in the morning), the screen was covered with pink and teal glowing pixels/artifacts. Dragging an open window (such as a safari window) across the screen seems to make the teal pixels collect on the white areas of that window, covering it in teal. Discussions on the Apple Discussions board led me to believe this was a problem with the new 30 monitor (http://discussions.apple.com/thread.jspa?threadID=221104&tstart=45). The only difference with most of those posters is that they seemed to have some thing they could do that would make the pixels dissapear for a short time (such as changing resolution, turning the monitor off and back on, etc.) They also refer to theirs as dancing pixels mine are stationary if I am not moving anything on the screen. Unable to get anything to work, I went back to my old 17 monitor on Tuesday. When I plugged it in, it now had the very same glowing pixels/artifacts on it as well., which leads me to suspect the video card. After a while the pixels have been joined by red and green ones as well. Pictures of the screen can be found here: http://jonberrydesign.blogspot.com/2006/08/macnightmare.html (click on shots to view them at full size) All OSX and software is up to date, and all updates, hotfixes, and drivers etc from the ATI site have been installed as well. Both monitors and the G5 are cool to the touch. Complete specs on my system: Dual 2 GHz PowerPC G5 ATI Radeon X800 XT Mac Edition Chipset Model: ATY, R420 Bus: AGP VRAM: 256 MB Here are the things I have tried with no success in even getting the pixels to disappear temporarily. In fact, they seem to be multiplying: Turning the energy saver off Turning the screen off and back on Rebooting the system Changing the resolution Changing color options in preferences Clearing the pram Lowering the brightness Installing Switch resX and lowering the refresh to 58Hz Blowing compressed air to clear all dust in ports and in G5 Reseating the X800 XT card Probably some other things Ive forgotten none has caused any change whatsoever in the offending pixels. Any suggestions from anyone before I call Apple and they blame the ATI card, or before I call ATI and they blame Apple? Help!