Basic questions about VR settings

After 19 months and approaching 500 hours I should know this, but I have some very basic questions about what video settings I should be using with VR.

I have noticed that usually the screen resolution setting in the Video Options screen reads "Windowed", but sometimes gives me a numerical reading like "1768 x 980" or "1920 x 1080". Should this be set to anything specific? Does it make any difference in VR?

My set maximum frame rate is set to "Unlimited". Is that the correct setting? Again, does it make any difference in VR?

After shadow quality, what graphics setting has the greatest influence on VR performance? Structure density? Vegetation density? Texture quality and resolution? Mesh quality?

I'm still trying to figure out why I get great performance with an Oculus, but not such great performance with either version of the Vive, regular and Pro. These questions are just part of that process.

Thanks,

Bill

Quote from kenventions

I bet it's because Vive uses SteamVR and the Rift does not - the Rift fakes better performance by processing the graphics at 45FPS and then fills in the frames to update the Rift at 90FPS.

That has been my assumption, but other people seem to get better results with the Vive than I do using similar machines, and I would like to know why that is! My benchmark scores all seem to be pretty good, so there must be a reason.

Yes.