I have always set windows up (since Win3.1!) with dual drives. One for the OS and one for temp files, browser cache, swap, spool, etc. I have monitored it with tools and the two drives seem to be about equal with R/W. I even did this with SSDs and it seemed make my computer run faster. I am planning my next build, and with the massive increase in nvme transfer rates, will I find any performance gains if I put in two NVME drives?