Some applications, such as MSI Afterburner and Meta-Trader 4 (MT4) do not display well on 4K monitors, they are just too small. This happens when the display is “scaled”: For some reason some apps scale and some don’t. MT4 is an old program so not a huge surprise, but MSI Afterburner is a graphics setup program, geez. Anyway, the fix is shown below, click on the apps EXE file and select Properties: