I've had a few weeks now to use this board and have come to some definite conclusions and some not so definite ones. My major problem was the system restart/shutdown problems many are experiencing here, but not using cpu-z or hwmonitor appears to have resolved that. Even accessing the BIOS has not caused any problems. I am, however, having some other problems. I am not yet using the board for HD playback of any kind, I plan on doing this at a later time. For now I am using the board for a personal pc/htpc. SD DVD playback looks great on a Pansonic 32" 720p LCD. No complaints there. I also use the pc for an occasional Netflix Watch Instantly movie, no complaints there either.
After using this system for a few more days, the problem persisted. It doesn't seem to be a heat issue. I've had this hang occur at varying times, so it's tough to diagnose what's causing it. The symptoms are clear -- the machine will appear to be running (power light is on) and the DVD drive will open, but there's no video, no hard drive activity, and the case LCD doesn't light up. If you use the power button to turn it off and then back on, it'll go right back to this state. I have to unplug the power from the power supply for it to boot again.
When you experience the hang are you trying to manually restart/reboot the pc or will it just hang at random times? I am having a problem with the video on my main monitor, (19" Hanns-G LCD) connected to VGA, just go dark. This seems to happen only if my Panasonic TV, connected via HDMI, is off. If I press contrl-alt-del the screen appears with options to log off, switch user, task manager, etc. but the desktop will not return unless I restart. At least the restarts don't hang anymore.
I'm thinking of trying the new 180.48 gpu drivers, and not using sleep/standby for awhile and see what happens.