Great job guys, Medium is awesome! In one of the updates a week or two ago, a glitch has occurred that sends lines all across the screen, most of my right eye is greyed out but ends abruptly to let my left eye see the sculpting area, and weird digitized looking gaps in everything. I'm on an AMD 390x. Thanks in advance!
Verify that you have the latest AMD driver by right-clicking on your desktop, going to AMD Radeon Settings, and looking at the system/overview tab. You should be on version 16.11.5. I have seen driver updates look like the complete but not actually update the driver correctly. This location in the settings has been a reliable place to check for me. Also, when doing driver updates I tend to uninstall the driver, reboot, install the driver, and reboot again.
What you describe was absolutely a known issue but was fixed in recent driver updates.