According to
https://rog.asus.com/forum/showthread.php?87380-Firmware-Update-for-ROG-SWIFT-PG279Qthere are issues with PG279Q that could be solved by updating a firmware in a service center.
I think I have similar issues with my PG248Q. It has several bright vertical lines on the screen when overclocked
There are also multiple horizontal bright lines(scanlines?) running across the screen when overclocked and there is a scene with low framerate. Doesn't happen without overclocking. There are no artifacts when refresh rate is set to 120Hz.
Is there a firmware update for my device? Or is it exclusively for PG279Q?