I have installed Rhino 6 Beta, and opened it successfully.
Unfortunately if I draw curves - they are all invisible.
But if I select an invisible curve, the selection is OK.
In the display panel - curves are checked.
Surfaces and Poly surfaces are well displayed.
What can be the solution to this problem?
Thanks
Rachel
Hi Rachel- just as a test, can you please try un-checking the setting for ‘GPU tessellation’ in Options > View > OpenGL page?
-Pascal
Yes, of course.
I have tried it and it solves the problem .
So - should it stay unchecked?
Hi Rachel, for now, leave that unchecked - developer Jeff LaSor has some related comments here
In particular
“So I’d like you to post a screenshot of Rhino’s OpenGL settings page so I can get a little more info about your Intel GPU.”
-Pascal
OK. Thank you very much.
How can I get my Rhino’s OpenGL setting page?
Hi Rachel - sorry - Options > View > OpenGL.
-Pascal
OK , I will try
Hi Rachelre
I had the same problem and it is OK after updating the display card driver to the latest edition. The curves are visible even with the GPU tessellation checked.
Hi Fwk
Thank you very much for your answer.
Can you please explain me how to make updating of the display card driver ?
Go to the NVidia driver page, download the appropriate driver for your card, install. These days it’s pretty easy.
–Mitch
As Mitch says.
It’s recommended, though, to uninstall your current drivers before installing new ones - from the Windows Control Panel > Uninstall a Program.
Dunno, 15 years ago this was pretty much required, but today? Personally, I’m pretty lazy, I always just run the installer. Haven’t had any problems to date, but I guess you never know…
–Mitch
I only do what @jeff tells me! 
What difference does it make whether GPU tessellation checked or unchecked?
Is it any problem to simply keep it unchecked?
Hi Rachel - no problem really, I think, it’s just slower. But if you can get the drivers updated, that’s probably a good thing regardless, and it may fix the GPU Tessellation problem as well.
-Pascal
Sorry, the open GL setting which is attached above is a mistake 
it is the Rhino 5 setting…
Here is the Rhino 6 Betta one:
Hi Rachel - yeah that driver is very old - I would update that for sure.
-Pascal
Yes I updated my drivers at Nvidia website, there are many other independent sites offering the drivers update but better to do it at Nvidia driver page. Nvidia does a scan check on your system to determine your card specs. So pretty straight forward, but then do back-up all your files. I did.
These days small updates in windows sometimes requires driver update… not sure if the installation corrupts the file or something…
Nvidia also updates drivers frequently so if anything goes wrong it’s worth it to check.
