I'm running Quartus 18.1 standard on Windows 10.
When I open 1 particular qsys project file, Platform designer appears to be running, but the screen updates intermittently and only around the mouse cursor. Menus do not disappear after moving the mouse away.
I installed Quartus 17.1, but had the same problem.
There is no problem with other project files.
I have the same problem with Quartus 18.1 on a MSI laptop with a Nvidia GTX1660Ti graphics card. My issue though differs from yours as follows:
I also have a laptop with a 2nd monitor, but the problem occurs on both monitors and with the external monitor disconnected.
I have Intel UHD Graphics 630 & NVidia GeForce GTX 1050 Ti.
An FAE suggested changing the setting as shown to fix issues with 4K displays, but this didn't resolve my problem.
I tried the FAE suggestion by applying the setting to 14 of the Platform Designer executable files in the "C:\intelFPGA\18.1\quartus\sopc_builder\bin" directory, and I haven't yet seen the problem manifest again. As the fault is intermittent in my case, it may be too soon to say for sure. I will reply to this post again if the problem decides to reappear.
The files I applied the setting to, are the following: