Blender 2.82a very slow compared with 2.79 I am coming back to use Blender after a bit of a break of a couple of years. I did a lot of work using version 2.7x. I am now trying to use version 2.82a. 

My PC is running Linux Mint 19.3 I have 32GB RAM, 16 Core Ryzen Threadripper 1950X and 12GB GTX 1080Ti. I have the nvidia drivers installed and I am using CUDA. 

What I find that for a modest sized model (approx 1M verts) version 2.79 is very responsive with zero lag. With 2.82a everything lags, not just zooming or moving the model but also menus and any selection can take seconds.This is in Solid viewport mode, so no textures or rendering.Render speeds are OK.

Are there any ideas as to how to fix this?

Thanks
Baz
I had this same problem and I found a few ways to fix this. By default, the resolution % in 2.8 is set to 100%, whereas it was always 50% before. This only applies to renders however, not really anything else. You can find it in the Output tab underneath your dimension. Another thing you should do is make sure Blender is using your GPU. In your Render tab it may tell you it's using GPU compute but you need to go into your Preference settings and make sure it is using Cuda. I found all this out this morning and my render times went from 2 minutes to 12 seconds, and my playback is a lot smoother.