Hey, I already made a similar post and uninstalled Zorin because I couldn't find the problem.
I reinstalled it and the problem persists. I have the correct resolution, but I can't switch to 60Hz; I'm stuck at 90Hz...
How can I fix this? Thanks.
If you have an Nvidia GPU, please make sure you install the driver for it, in Software & Updates, Additional Drivers.
Again, if you have Nvidia, and you installed the driver & restarted the computer, now go to Nvidia X Server Settings, and set the refresh rate there.
If you don't have an Nvidia GPU, and your's is AMD, or Integrated Intel, you may try to set the refresh rate in Compiz...
