Weird color boxes inside the image in Photoshop

First, try disabling GPU in the Preferences (Performance preferences). Any better?
If not, go to Preferences > Technology Previews... and check "Deactivate Native Canvas" - then restart Photoshop. Better?
If not, recalibrate and build a new ICC display profile, the old one might be corrupted.
If you are using software/hardware for this task, be sure the software is set to build a matrix not LUT profile, Version 2 not Version 4 profile.
If turning OFF GPU works, it's a GPU bug and you need to contact the manufacturer or find out if there's an updated driver for it. On the Mac, that's part of the OS update(s) so if this is the latest OS version, you may need to roll back a release.
Also see: https://helpx.adobe.com/photoshop/kb/acr-gpu-faq.html