Do better graphics cards make a difference to the NEW 8.1 Lightroom classic cc?

The Develop module is not intended for browsing. That being said, Adobe improved the pre fetch logic for loading images into the Develop module cache back 6.x cycle and have continued to tweak it in some subsequent releases.  Systems having 16GB or more ram  benefit most from pre fetching as more memory can be allocated to same. However, pre fetching is only viable if you browse the photos in the filmstrip sequentially ( e.g. photo 3, 4, 5, 6...). If you're in the habit randomly selecting photos in filmstrip then the improvement that pre fetching offers is largely lost.

curiouscat951  wrote As above. I am using GTX960 2Gb now. Any benefit upgrading to 1060 or RTX series? Browsing in develop mode and zooming is very slow, despite having built Smart and Full previews, on full SSD and 32gb RAM setup.

The graphics card does not affect speed of browsing in the develop module, and I don't think it affects the speed of zooming either. It only affects the speed of performing develop operations like changing a slider. SSD, memory and full previews also don't affect the speed of browsing in the develop module or zooming. Number of images in the catalog does not affect develop module speed. I think this is all controlled by the speed of the CPU, not GPU.

Do your browsing in the Library Module and not the Develop Module, and things should go a lot faster, because the Library Module will use your full-sized previews, while the Develop Module does not.

The above is not a statement about Lightroom 8.1 specifically; it applies in general to LR 6 and above.

What are your Camera Raw Cache Settings in Preferences > Performance? With 32GB of RAM you can bump that up to see if the performance is improved. How many images are in your library?