I'm going insane with GPU noise.

Hi, i recently bought a pair of Yamaha HS7. my first studio monitors, and i'm very happy with them.

Problem is, the moment i turn on the PC, the speakers start to output noise that matches the GPU activity, like when i scroll, open images, play games, even in idle. I can hear the noise from the PC even with the speakers turned off, so it's not a speaker related problem, the problem is the GPU.

The GPU is an AMD 6750XT, how can i isolate my USB audio interface from the PC?