I'm currently running an MSI R9 290X, MG279Q, and Dell U2412M.
When I run only my MG279Q over displayport, Freesync works perfectly.
When I run my MG279Q over displayport AND my U2412M over DVI, Freesync no longer functions on my MG279Q. The option is checked both in the AMD drivers and the monitor's menu, but the refresh rate does not sync to FPS between 35 and 90 FPS (confirmed in multiple games as well as in AMD's Windmill Freesync App).
I enjoy Freesync, but don't want to give up my second monitor. Help!