Spanners,
Recently had trouble with Abit BE6II Mboard, had to send it back, occasionally it wouldn`t power up and display somtimes corrupt when it did decide to power up. It eventually gave up and wouldn`t even switch on ATX supply in case. New BE6II fitted, no problems. It does seem that the BE6II is a little fickle compared with the original BE6.
If you havn`t elliminated the RAM as a possible suspect as previously suggested, I have a 64Mb stick you can try just to narrow down the culprit of the frozen screen.
Regards
Wiggly Amp