Taken from the ROG forum
I noticed several people having the same problem with screen flickering on this monitor, as I had
I have 3x R9 290X in crossfire and 144Hz flickered to the point where it was unusable, but I found a workaround.
I used ToastyX's Custom Resolution Utility (CRU) to create a custom timing at 144Hz that eliminated the flickering for me. I dumped the timings from the EDID using Linux since the CRU doesn't recognize the extension block used in the Swift.
The timings for 144 Hz are the following according to the EDID:
Active: 2560
Front Porch: 4
Sync Width: 16
Back Porch: 2
Active: 1440
Front Porch: 1
Sync Width: 1
Back Porch: 7
Pixel Clock: 538.8 MHz
I added these into the CRU for the EDID override just to make sure they were correct, and they were. The monitor was doing the same strange flickering.
I then started to tweak the timings slightly and i noticed some improvement on the image when increasing the sync width and other things. For me, what eliminated all flickering was the following timings:
Horizontal:
Active: 2560
Front Porch: 8
Sync Width: 16
Back Porch: 16
Vertical:
Active: 1440
Front Porch: 1
Sync Width: 1
Back Porch: 7
Pixel Clock: 542.58 MHz
This has slightly more sync timings at the expensive of a higher Pixel Clock, but the monitor seems to handle it fine, and there is no more flicker @ 144Hz! I tested and there is no frame skip or any such thing, so the refresh rate appears correct.
Those of you who are having this problem try this out and see if it fixes it for you.
On my phone but I will see if I still have the driver tomorrow Greg.