depends on what your mobo options are for upgrading. with my Asus P5n-E i am able to download the latest BIOS file from ASUS and put it on a usb stick and then i can go into bios and upgrade it that way. the only other way i know of is loading it via a floppy disk
it's really simple
1.put your new bios file in a directory where you can easily find it,after you have extracted it form the zip,it should be like so :xxxx.bin,ie it is a binary file,,
2,your board comes with a util called asus update,install it and follow the instructions for flashing from a file,,
you might be given the option to save the original bios,your choice,,
upon reboot go into the bios and make sure everything is as it should be,some folks reset their bios before flashing,again your choice..
note:flash with the oldest cpu just to be sure..
totally agreed with Zorg, flashing bios through windows is so risky, if something goes wrong such as a power failure or your internet connection dying or BSOD or whatever, good chance your mobo is gone as most BIOS chips these days are soldered on directly to the mobo.
ok, updated the bios. everything seemed to go well. bios said it was complete and that it would restart in 5 seconds. however, upon restart, it didnt post or anything. now I get nothing fans spool up, thats it.