I've had this annoying flickering on my monitor every time I open Thunderbird. The screen would sporadically blink in and out of existence. I've seen the same problem in other programs, but Thunderbird was the most prominent. It was usable, but annoying. I just accidentally found the fix and wanted to document it in case others are experiencing the same issue.

First,let me tell you a bit about my setup:

I'm using a desktop Windows computer with an AMD Radeon 7750 video card.

The DisplayPort out of the video card goes into an AdderviewPro Displayport KVM Switch.

From there, the KVM Switch connects to a Dell U3011 30 inch Monitor. The monitor resolution is set to 2560x1600.

When the blinking occurred, I always thought it was due to the KVM Switch. I've always had mixed luck with KVM Switches--but when you have multiple computers at your desk I think the benefit outweighs the problems. [Other computers connected to the KVM Switch do not exhibit the same blinking problems].

I was reading up on some completely unrelated problems with my Surfacebook's dock and decided to dig into the blinking issue. I was wondering if changing the refresh rate would have an affect. I poured over options in the Radeon Settings panel:

Nothing seemed to make sense. Then I clicked the "additional settings" button:

After that, I noticed the preferred color depth setting. It was set to 10. As an experiment I changed it back to 8. Immediately all the blinking problems were gone. I'm not sure what the affects are from setting the color depth from 10 to 8. As best I can tell; the computer appears to be working as expected. I'll keep an eye on it to see if I run into any problems.

I've been using this for a while now without any problems. I have to admit I'm pretty shocked. I'm not sure what is more frustrating; that I lived with this for so long and it had an easy fix or that the problem existed in the first place.

Hopefully this helps someone.