Some games are forcing my monitor to change it's refresh rate from 60htz to 50htz, which wouldn't be a huge issue except most of these games don't behave correctly when vsynced at 50fps instead of 60. This even affects windowed and borderless windowed modes
The main culprits are;
Crysis trilogy (can be "fixed" with a custom resolution of 1920x1078@60htz although Crysis 3 still locks at 50fps regardless)
Crash Bandicoot NSane Trilogy
Prince of Persia Forgotten Sands.
System specs
Ryzen 7 1700 @stock
16GB 2400mhtz 4 sticks DDR4
Radeon RX480 8GB @stock
S22F350 Samsung monitor connected via HDMI
Gigabyte GA-AB350 Gaming
Windows 10 Pro x64 (1803 17134.228)
Catalyst 18.7.1.