GPU not shown after VBIOS flash!

Hello, i have a rig with rx470 all are same cards, same memory,etc… everything was running smothly.
One of my cards was mining at 21mh/s while others at 18mh/s. I was wondering why is that, so I downloaded both of the rom files and compared, the one running 21mh/s was overclocked, the other not. So I used the same rom file to overclock the other one which it booted and I got this kind of error:

18m 42s - Autofan: GPU temperature 511 is unreal, driver error
04:00.0 Temp: 511C Fan: 42% Power: 16777215W

And after that that gpu is not showing in the panel!!
So, did I brick it? Is there any solution to restore to the orginal rom, since I do have it.

Thanks in advance.