Question My gpu doesn't work on my other motherboard but works on my older one

[IbnKarim]

Long story short everything worked fine on both my new prime b450m-a ii csm mobo and my old h81m-k, until I flashed my gpu vbios, so I found a way to flash it back to my original rom thru my old setup with igpu, and now my gpu works again with the drivers and everything but when I install it on my latest prime b450m-a ii mobo, the gpu doesnt spin and it doesnt boot up, but when I install it back to my old rig it works. Do note that my latest mobo lits up so its working and the cpu fan spins, only the gpu doesn't for some reason. I've tried reinstalling new Windows and Uninstalling drivers with DDU and I've also tried removing cmos battery from the new mobo and reseating rams, gpu and the wires plugged into the mobo and it still doesn't work it is strange that it only works on my old mobo

 

[IbnKarim]

Long story short everything worked fine on both my new prime b450m-a ii csm mobo and my old h81m-k, until I flashed my gpu vbios, so I found a way to flash it back to my original rom thru my old setup with igpu, and now my gpu works again with the drivers and everything but when I install it on my latest prime b450m-a ii mobo, the gpu fans doesn't spin and windows doesn't boot up, but when I install it back to my old rig it works. Do note that my latest mobo lits up so its working and the cpu fan spins, only the gpu doesn't for some reason. I've tried reinstalling new Windows and Uninstalling drivers with DDU and I've also tried removing cmos battery from the new mobo and reseating rams, gpu, and the wires plugged into the mobo and it still doesn't work it is strange that it only works on my old mobo.

Specs:
rx 580
32gb 3200mhz gskill ripjaws
Prime b450-A II
P650b gigabyte

Old rig
Rx 580
I5 4460
Asus H81m-k
P650b gigabyte