這裡有測試報告
http://www.tftcentral.co.uk/reviews/asus_mg279q.htm
裡面也提到這問題現在已經解決了
144Hz Frame Skipping Bug = Fixed

When the MG279Q was first released, a few early samples started to make their way out into distribution, mostly on mainland Europe. At the time, www.sweclockers.com tested the screen and found a bug when running the screen at 144Hz refresh rate. It seemed to drop frames for some reason at this maximum refresh rate. Stock was recalled from distribution and a firmware update was carried out by Asus. This is one of the reasons why our test sample was delayed and why the screen has been a little late making its way out to customers.

We are pleased to confirm that an updated firmware has been applied to the screen and the issue has been fixed. We confirmed this from an AMD and NVIDIA graphics card at 144Hz. All stock available to buy now/soon should be the updated version. Only a small hand full of very early units were affected, and we would suggest contacting Asus support if you have one from the very early batches and are experiencing problems.