I've been running Debian sid/unstable on the 939 variant of your board since January w/o problems except the known forcedeth issue w/ warm starts after coming from Windows.
Look at the long 430 thread below to see more examples of boards that work.
BTW, if you use ECC memory, please take a few moments to complain to
tsd@asus.com.tw and ask why there aren't any manual ECC settings for scrub time, etc...the BIOS only has an ECC Auto/Disabled setting. The 939 board has lots of manual settings...