Windows won't boot when connecting my GPU

[super_halta]

Hello,

I bought new GPU (Asus RX 580) using Asus Z270-P motherboard , since i bought it the system had very high CPU usage 99% or so ! now the windows wont boot when the GPU is connected , but if I connect other GPU same model (RX 580) it boots fine and works normally !

Note: I modded the GPU for original BIOS but still the same issue

What can I do ? will the warranty still works , as I modded the BIOS before

THanks

 

[Rogue Leader]

What did you do to the BIOS?

The warranty is gone if you mod the BIOS, yes they can tell.