This is something that used to happen occasionally in SW2008 at the end of the day when I was driving SW all day long. Now that we are on SW2011 I get this all the time. Very annoying and makes in-context selections difficult.
The sketch face that you are placing hole wizard holes on consistently turns dark gray, almost black. This is on my Dell T3500, Windows 7 x64, SW2011 any SP. I happen to be test driving a Quadro 600 at the moment, but it happens with the 2000, 4000 and 5000 as well. I have the approved SW video card driver for my set-up.
I am not sure if this happens with the AMD/ATI FirePro's. I may have some time to check in the next week or two with the cards I have to test drive.
Anyone else seeing this? Is there a fix? Is it a Quadro issue or a SolidWorks issue?
See attached image for what I am referring to.