This is something we’ve been evaluating pretty heavily lately and may have narrowed down the culprit AND have a workaround until we get it fixed.
We seemed to see an unusual number of slowness issues on machines with very powerful specs; specifically on computers with pro-level video cards (Quadro, FirePro). The issue can be described as “It takes a long time for my models to load… longer than it did on my old machine”.
If this issue sounds familiar, please try this.
If your Materials tray is open, try keeping it minimized except for when you need it. Also, when you close SketchUp Pro, make sure that the Materials tray is not expanded. It can be in your tray, but not open where you can see the folders in it. It also seems to affect the speed of SketchUp’s functionality over time.
If you conduct this experiment and see a difference, or see NO difference in load times, please let me know and I will collect some additional info from you. We look forward to getting this issue fixed for good soon.