This is happening more and more to my iMac 27". There is a pattern of dead pixels (or something) as seen in this image.
That is a screenshot of a white background Photoshop CS5 document zoom level 33% at 300DPI, RGB color mode.
Over an image:
This is extremely annoying and started happening a couple weeks ago. I've deleted my Preferences file and it still happens. Anyone have any idea what this is? It only happens at certain zoom levels. If I zoom in a lot or stay very zoomed out, it is not there. This pattern is the same across multiple documents and it's driving me crazy! It looks like confetti over my documents and it is making image editing very difficult.
This appears to be graphic corruption. Let's do this test:
1. Go to Photoshop>Preferences>Performance.
2. Uncheck "Enable OpenGL Drawing", click OK.
3. Reopen the image.
If the behavior goes away, it is time to uninstall and reinstall the video driver for your video card.
Worked like a charm. Not sure how you knew that but thanks a lot!
Random pixels like that usually mean a bad GPU or bad VRAM on the video card.
You're likely to see them in any application that uses the GPU.
And the only good solution is to replace the video card.