Latest Flashmenu from the abit site, attempting a flash from bios v19 to 20, under 32 bit Vista.
Got to DMI programming (I think, if not DMI then something similar), 56%, and then froze. I left it there for five minutes or so with no change (and the mouse had frozen), before rebooting. No POST at all now, not even a beep.
I've successfully flashed this board up to v19 using Flashmenu, so I wasn't expecting any problems.
What's my next step?