When i play Overwatch at Low quality i only see that cpu load 100% and RX460 some time "run for fun" run up to about 80-90% for 5 seconds and them return to 0%, all i see when i use only onboard, gpuload 100%.
Fps when i use onboard card is about 22-26 fps but not drops too much.
Fps when i use RX460 card is about 10-48 fps drop 20-25 fps (more than onboard card).
I think i have a problem with driver or software.
Ps: I try my RX460 on another computer it work really good, with high quality in Overwatch, fps is 90-100 fps.