Been looking for a solution to this problem since I received the lovely Asus MG279Q for my birthday in November. I've heard similar reports from people all over (with this monitor, and others), contacted as many of the parties as possible, and have had no solution thus far.
Here's an album of the problem I'm experiencing: http://imgur.com/a/GliiO
Anther picture from another user reporting the same problem: http://imgur.com/3l41vqP
Only under two game engines have I experienced this problem, Unreal Engine 4 (reliably in every single game powered by it), and The Division (Snowdrop Engine). Its easy to reproduce, simply set the game to native fullscreen, and when the game launches, you sometimes experience a shift on the left which corresponds to a repeat of pixels in the centre of the monitor. Normally I would assume fault with the monitor, but simply changing resolution from native and then back to resolves the problem.
Occasionally going back to desktop after closing a game will result in the problem persisting through to the OS. Again, a simple resolution switch and switch back usually solves the issue.
Thus far I have contacted:
Asus - Not a fault with the monitor, they suggested contacting AMD and Epic Games (this was prior to The Division beta).
AMD - Two bug reports, and this (which was suggested by AMDJoe over at /r/AMD).
Epic Games - Attempting to contact them to see if this is a game-centric issue.
Drivers I have tried:
15.7, 15.10, 15.11.1, 16.1, 16.1.1
Asus MG279Q and Samsung S24B350 (Asus as main)
R9 290 with 16.1.1 driver
16GB of memory
I'm not sure if this is a result in the strange Freesync frequency of the MG279Q and other monitors with similar scalar ranges (35 ~ 90 Hz), but would really love for this to be resolved.
Would love for this to be resolved for myself and many others suffering. Any thoughts and information would be welcomed!
Added system specs