2012-03-20 graphics glitches on OS X Lion

Graphics glitches

For the past days, I've seen a number of glitches on OS X Lion (update 10.7.3) with my mid-2010 Macbook Pro, and apparently, I'm not the only one.

It seems to happen especially on external monitors:
https://discussions.apple.com/message/17524501#17524501

However, iMacs have a lot more trouble:
https://discussions.apple.com/thread/3201871

A possible solution for the graphics glitches is mentioned at the end of the thread:
https://discussions.apple.com/message/17804906#17804906

White screen

UPDATE: this issue seems fixed with the 10.7.4 update

I've encountered a bug where the screen would blank, reproducible as follows:

Black screen

I've also encountered a bug where the laptop screen would just stay black, not reproducible. I took the following steps:

Remotely I could log into the laptop, though.

Another set of circumstances happens as follows:

The following lines are then visible in the kernel.log:

 --- last message repeated 1 time ---
 kernel[0]: NVDA(OpenGL): Channel timeout!                                                
 --- last message repeated 1 time ---
 kernel[0]: NVDA(OpenGL): Channel timeout!
 --- last message repeated 1 time ---
 kernel[0]: NVDA(OpenGL): Channel exception!  exception type = 0xd = GR: SW Notify Error
 kernel[0]: NVDA(OpenGL): Channel timeout!
 kernel[0]: NVDA(OpenGL): Channel exception! exception type = 0xd = GR: SW Notify Error
 kernel[0]: NVDA(DisplayBase): Channel timeout!

UPDATE: this is still occurring with 10.7.4 update. Workaround is to keep the lid open