I am using Rhino Version 6 SR29 (6.29.20238.11501, 25/08/2020). After the most recent update, I noticed that my Rhino 6 displays fragmented/distorted geometries which was not the case before. I tried the same file with my Rhino 5 and worked fine. Here is the screen shot for comparison.
Similarly, if I create a brand new file in Rhino 6 and draw a box, the process for which I set box corners would show but the final geometry is not viewable. I doubled checked my display setting to ensure surfaces are checked. Here is the screen shot for reference.
Hello - please try resetting your display modes to defaults in Options > View >Display modes
Also, please run SystemInfo in Rhino and post the results.
Lastly, see if disabling Rhino Resurf in Options> Plug-ins page and then closing and reopening Rhino helps - I doubt it, but worth a try.
Hello - You’ll need to make the NVidia card the primary display - in the Nvidia control panel you should have a setting to use ‘high performance’ rather than battery saving. In addition, please update the Intel driver to the latest from the Intel website.
If none of that helps, please try disabling the following plug-ins, in Options > PlugIns page, then closing and restarting Rhino: