Hello, it seems to me that, indeed, this is a typical case of " Improved graphics performance: "
In general, this goes back to normal when this option is disabled. (associated with the correct driver of the graphics card and/or the installation of the patch proposed by Solidworks... Patch to be reinstalled after any changes to the driver). The RTX 4000 card is eligible for the patch... https://www.solidworks.com/fr/support/hardware-certification/
FYI, I re-checked the " Improved graphics performance" option because I had a strong slowdown of the software. I must be one of the 1% of cases for whom this option works as it should
otherwise I still have my initial problem... with or without the option
Otherwise try to open the assembly with SW rx and the safe mode in " emulate functions " mode to see if it comes from the driver, or in " ignore tools/options " mode to see if it's a question of parameters/options? This makes it possible to diagnose possible sources of bp!
Try it out by pushing the quality options to the max, boxes and sliders, to the edge of the red zone and/or to the max. Then everything at a minimum and unleashed if not better.
Another clue is the " definition " of the GPU in the registry:
What are your Renderer and Workarounds values at this address: Computer\HKEY_CURRENT_USER\SOFTWARE\SolidWorks\SOLIDWORKS 2020\Performance\Graphics\Hardware\Current