I have 2 graphic cards intel hd graphics 530 and NVDIA Ge Force GTX 960M I use NVDIA on only games
the intel is mostly irrelevant since nearly all mainboards have such an onboard gpu nowadays but that doesnt really count as a 2nd gpu. its useful/neccessary in case ur gpu dies but thats not really an actual gpu unless ur comparing it to those who are 20 years old by now.
also, the onboard is not used when u have a dedicated gpu. wouldnt work anyways since its 2 different hdmi slots/lanes.
if ur drivers are up to date then its mostly nothing u can do anything about.
u could try to do a clean driver reinstall in case something went wrong before but usually AMD is more susceptible to that than nvidia.
u could also try resetting the directx and GPU cache, especially the directx one since GPU cache is usually reset on driver reinstall. u can try both, though.