you can use any 512k bios (or resize a 256k) as long as it works with your version of xbox. if you have a 1.6, you can only use a newer x2 bios (5035 is the latest) or an evox m8 bios (use evox m8+). if you have a 1.0-1.5 you can use any newer bios, including the ones above (make sure to use the one labled for older motherboards).
you edit the x2 5035 bios with x2ool or x2 config maker. you use evtool for the m8+.
AND NEVER USE THE X3 BIOS IF YOU DONT HAVE AN X3 CHIP
