This is a buggy OptiX issue I have been having on Blender even though I do have an RTX 2070 and have updated to the latest Nvidia drivers and even tested on various Blender versions. What happens when I switch Denoising on OptiX it keeps giving me Loading render kernels (may take a few minutes the first time) eventually it crashes. After spending hours figuring this out, my be way around it is not have the OptiX on but rather switch to OpenImageDenoise on Viewport setting when you load Blender or before you do any rendering.

1. Load Blender, before selecting Viewport Shading to Cycles, go to Render Properties [...]