As long as its the 5770 one you just need to prog to flash it over, theres winflash and atiflash that are windows based and work well. You need to be 100% that the bios is from a 5770 though dude.
You will get the option to back up your bios before you flash it Im pretty sure of that. That's how people get them off in the first place dude.
A while ago I was collecting Alienware bioses. My friends were backing them up and sending them to me and then I was decompiling them and pinching all of the logos and DMI entries
hmm it does not seem to wanna work,never mind i dont wanna push this card anymore anyway,i have a feeling ile be moving back to the green team soon,so i wanna keep it all intact.