Hey all - first time Retroarch user here, but i’ve been hearing great things from friends 
I managed to setup a controller and some other options and was getting ready to load roms and be off to the races, but having a bit of trouble getting fullscreen to behave.
I run a custom resolution on this machine, as the monitor is a Mitsubishi DLP TV that overscans quite a bit with the native 1920x1080 resolution and can’t be adjusted on the TV itself. The custom is currently set at 1768x992. When I load retroarch, I can navigate the different screens without issue. When i enable fullscreen (windowed or not), there is a horrible flickering several times a second, making the menus/GUI nearly impossible to navigate or read. I’ve played around with the vsync settings, viewport, etc but can’t seem to find anything that works.with the custom resolution.
Changing the OS resolution to 1920x1080 fixes the issue, but creates another - can’t see the whole screen. Not a huge deal for playing games, but it moves the start button off the screen entirely. I’m not dead-set on running 1768x992, but keeping as close to that as possible and smaller would be best if something else would work.
Any suggestions or advice would be greatly appreciated. Machine specs below, let me know if i’ve left out anything
AMD A10 6800k 6gb Nvidia 750ti Windows 10 64bit