I am browisng and applying all solutions since few days and trying to adjust the system but this is beyond "settings" and since "Legacy compositing" has been disabled we are all sitting ducs now. Please provide an actual solution since this is the most ridiclous subscription I have ever signed up for. On same machine C6 blows 2020 out of the water in startup and reacton time. CC should be able to handle anything with the assigned RAM and GPU power:
Had same issues. Turned out its becouse of G-SYNC problems with Adobe software. If you are using any freesync or gsync feature try to disable it. Not sure if its related with your problem but I have to share this here.
I'm having the same problem and a lot of brush lag. It's unbearable, I havn't been able to get any work done all week and have tried updating and uninstalling several versions of photoshop with no improvement. Might have to go back to CS6!