Question Dual GPU video card using only one GPU with crossfire

[drambit]

I'm setting up an old system that hasn't been touched in a few years, video card is an ATI Radeon HD 5970. Both GPUs show up in device manager, MSI afterburner, and GPU-Z, and UCLS is turned off, but for some reason when I play video games the second GPU always sits at 0% usage and does literally nothing.

I'm on the latest drivers for this card and have gone through my AMD settings to make sure everything is square, it seems like everything is. 2 hours of diagnosing and googling seems to have gotten me nowhere though, almost all the people who could only get one GPU to work had some more blatant problem like the computer not even detecting the second GPU, or crossfire being outright disabled. For me there is no error and everything looks good on paper.

OS is windows 10 64 bit.

Any ideas on how to fix this"?

 

[Barty1884]

What games are you playing? If there's no CFx support in the specific game, enabling CFx via software etc won't do anything...

 

[drambit]

What games are you playing? If there's no CFx support in the specific game, enabling CFx via software etc won't do anything...

I tried a few games, most notable of which project cars 2 which has excellent crossfire support. 0% usage on one of my GPUs. It's not spitting out any errors so frankly I'm not even sure where that begin in terms of diagnosing the problem.