Make a DOS disk.
You said in another post that you've been building and repairing desktop computers for years, yet you've never flashed a BIOS?
I don't know how to respond to that. As a tech professional that's been dicking with PCs for over two decades, I am aghast.
There are two files you need to download: The BIOS image file and the BIOS Flash utility. Find them here: http://www.via.com.tw/en/products/ma...erboard_id=202
Create a DOS disk. put both those files on it.
Run the executable file with the name of the BIOS image as a parameter.