I read much about the issue concerning my mouse pointer: after some hours of PC usage, it become corrupted.
The issue regards both v16.7.2-whql and v16.7.3 Crimson driver, according to many users even the beta drivers.
Temporary solutions are:
1) Start Magnifier in backgroun, but cursor completely disappears in games, so if you want to have fun you need to follow the second step;
2) Reboot computer.
I'm sure that's not a subjective report, but I hope to sensitize AMD to consider bugfixing the issue asap, or I'm sadly forced to refund my wonderful RX 480.