Enabling 144hz for Asus PG278Q on AMD gpu

[ToastyX]

The problem is AMD doesn't allow horizontal blanking less than 56 because it breaks their HDCP implementation with newer cards, and the monitor won't accept horizontal blanking greater than 40, so there's no way to make this combination work without disabling HDCP and modifying the driver. AMD puts the blame on the monitor for not supporting standard timing parameters.

The memory clock issue with low vertical blanking has nothing to do with your problem. The memory clock can't change if the vertical blanking is too low because there won't be enough time to retrain the memory without corrupting the screen contents. What is the lowest vertical blanking that the driver will accept with your RX 5700XT?