Try turning your monitor off and then back on to see if it comes back. I had a weird issue like that initially but eventually it stopped doing that and I'm not sure what actually fixed it. It may have gotten fixed with the later drivers but I'm not sure of that. I had forgotten about it until you mentioned it.
Below is what I wrote in an earlier post.
Edit: Okay, I discovered that I lose the video signal or rather my monitor shuts off but turning it off and back on, things are fine. It's like my monitor goes into sleep mode. After upgrading to 77.77, instead of hitting reset when it happened, I just turned the monitor off and back on. Madden was still running and things were fine. Overall, SFR still works for me with the 77.77. The performance is a little lower than the 77.76s but other than that, they seem fine.