I have a MSI K7N420D and it's slow and crashes alot. The sound on it is not really 5.1 it's semi.1, and unless you have two sticks of ram, your onboard video sucks too
You wouldn't have those problems if you knew how to build a system properly. I have the same board and it is fast and has never once crashed. Dolby Digital 5.1 works great, and the video is better than any integrated video ever created. All my friends love this thing and are building their own NF2s as soon as they are available.