Organ: you must just be lucky, I fix computers as a job, and come accross many driver conlifctions and problems that can have very strange side effects, also I know the BIOS isn't at all a windows driver or that related, but I normaly check for BIOS updates while checking for driver updates, as they cna have just as large implications.
Also just ask anyone who's had problems with ATI's GPUs, they frequently can cause BSOD's with simply bad instalations, or just a speisifc version of the drivers, much more finikey than you'd expect, I should know I've had such problems as stated :P