It would be nice to see your stats because I have an RTX 2070. You should be able to get it hit 80% usage if you have things setup correctly. I see a lot of problems with AMD CPU and Nvidia GPU combinations. Have you tried a BIOS update?
Yes I have everything set up for GPU acceleration, but it's just not working. I did overclock my GPU and it does cause some trouble with Photoshop and Lightroom, I'm not sure if Premiere is the same case. But I tried turning off MSI AfterBurner which usually causes problems for Ps and Lr but Pr is still not fixed. Can you show me your BIOS settings?
I think I have 14.5 and it works perfect on my system. That being said it would not hurt to flash the BIOS because Windows 10 is always making updates and Adobe wants the current version of Windows. Having said that Premiere Pro does need to be tweaked more than Avid, FCPX, Edius, Resolve etc.