did u backup your original bios before you flash?
i brick my 7970 before cause i flash 7950 ghz instead of 7970. wat i did was i put another random card to boot and my 7970 as 2nd card. and reflash to the intended 7970 ghz bios
you may find your bios here, not sure which model your card using
https://www.techpowerup.com/vgabios/
Help BIOS!, HD 7970 DC II