don't worry about my other post i fixed it i went back to an older bios. 4975

anyway the way i've been flashing the bios is through evolutionx. the flashing works etc...
i have 3little buttons on the front of my xbox with an led (a little control panel) and from left to right it goes. turn chip on/off
enable/disable flash protection
bank1/bank2
hence, when i go to flash my bios (throgh evox) whether it be 256k or 512k, it will flash onto both banks which is bad since i want 2bioses. (1 on each bank eg 4977 on bank 1 and 4975 on bank 2)
but i don't know how to do this?!?
how do i only flash 1 bios to one bank?
and how big is each bank?
is it possible?