Hi. I started a new .blend file in 16.2.6 and after modeling a relatively simple mesh
I did some interactive renders and noticed what I thought looked to be high Vram
usage. I saved and opened the same .blend file into 15.3.1 stable and indeed there
was quite a difference in Vram usage, over 1000M. I previously reported having the
same issue between 15.1 and 14.0 back in April, 2018.
(Current Nvidia driver 398.82)