Flickering green and blue pixel problem
- Green sprites or snow on ATI X800
- 30 inch with flickering blue pixels
- 20 " Cinema Display with vertical green line
- New 17" PB + 30" Cinema. Random Pixel Problem
- 30 inch screen issue?
I got a brand new Dual 2.5 GHz PowerPC G5 with a nVIDIA GeForce 6800 Ultra graphics adapter with 256 MB VRAM and a 30' Cinema Display. During original setup after about 20 minutes I discovered flickering pixels on the desktop background. In the top and center area of the display they are green and in the bottom area blue. When I change the desktop background from Aqua blue to a solid color they go away.
We talked to friends who have the same hardware configuration. They had the same problem with one of their computers and solved it by replacing the nVIDIA graphics adapter. We talked to AppleCare and they sent us a replacement graphics adapter. I installed it and first it looked as if our problem had disappeared. However, after working for an hour the problem appeared again. This time there were more blue pixels than green one in the bottom area of the screen.
To find out the source of the problem I did some tests:
1. It also happens if I play DVDs.
2. The longer I work the more pixels I get. Flickering pixels turn permanent. Over time it starts looking like a night sky with blinking stars.
3. When I turn off the display for some seconds and turn it on again first the pixels are gone but after some seconds they begin to appear again on the exact same place they were before.
4. After a certain time pixels also appear in the dock and in the icons on the desktop.
5. If I move a window near the pixels they disappear as soon the window shadow moves over them.
6. The pixels on the desktop background vanish if I change the desktop to a solid color.
7. I made screenshots of the Aqua blue and Aqua graphite desktops and open it using Preview. The flickering pixels appear there, too.
8. On the Aqua graphite background there are much more green pixels than blue ones.
9. If I move the Preview window containing the screenshot of the Aqua blue and graphite backgrounds the pixels jump. If I move the window 1 pixel to the right, the green and blue pixels stay in the same area but change position. If I move the window back 1 pixel to the original position, the green and blue pixels change back to the original configuration.
10. If I find myself an easy to recognize configuration of flickering pixels and move the window exactly 8 pixels to the left or to the right the configuration reappears!
11. Even after a restart the pixels seem to appear on the same places of the background.
12. When I first discovered the problems there were two green pixels in the center of the screen. Even after I replaced the graphics adapter with the new one I at least once saw two green pixels which appeared to be at the exact same position as with the original graphics adapter.
13. Joggling the graphics adapter connector cable does not affect the flickering and/or position of the pixels.
14. Others reported it only appeared after they updated to 10.3.8.
15. Others reported it also happened with ATI graphics adapters.
16. Others reported the problem went away with ATI graphics adapters when they updated their ATI drivers.
17. Sometimes I have green pixel configuration directly on the left side of a window over the Aqua blue and graphite desktop backgrounds. They all are on a vertical line in the shadow of the window. When I move the window down or up the green pixels stay at the same place on the background. If I move the window one pixel to the left or the right, the configuration changes.
18. Two times the problem suddenly disappeared completely and only slowly reappeared minutes later.
Some possible causes:
C1: Hardware defect of the graphics adapter.
C2: Hardware defect of the computer's mother board.
C3: Software problem of the graphic adapt