Yes I did it by downloading the most recent bios version on my iMac and putting it on a fat32 4Gig stick, plugging it into the usb port of the mobo and go into bios at start up and us the flash utility or update bios option there. I forgot the name Qflash maybe, I can't remember but it's right there at the main title screen little option. Then you can update or flash via USB.
[VIDEO]http://www.youtube.com/watch?v=yFLRCwhjujM[/VIDEO]