1. 16.12.1
2. BenQ XL2730Z - DisplayPort
3. Latest Windows 10 Build
4. R9 290
5. Just enable or disable within the Driver, monitor only has OSD info Freesync on or Off
The difference here would be the connection method(well monitor to). I have a spare 290 as well where the issue happens. It also is further backed up by the number of posts around the net with similar issues all connecting through HDMI but i cannot find any where the monitor is connect through DP. Atleast it removes a worry i have about a new monitor im looking at.