I went thru the same with the IDE DVD-ROM when I installed the CD-ROM that came with mobo, then installed BETA 16.B04 BIOS.
Then I switched to BETA 16.B09 BIOS and d/l the drivers from Neely's Post #1 and miraculously it started working

@Ace, just want to thank you again with the 40mm fan idea to cool the PWM