Ubuntu Recognizes my Graphics Card but does not perform properly Nvidia RTX Ubuntu Mate 18.04.2 LTS

I have an Nvidia RTX 2070 with 8GB of VRAM on Ubuntu Mate with Nvidia Driver Version 415.27 but for whatever reason when i turn Blender on and work on a project that Exceeds 500,000 - 1,000,000 Polygons (which happens often) Blender lags because it cannot handle the Load on the GPU - and the GPU goes all the way to 70% - 80% usage - i got a gauge of how powerful my GPU is from this website : https://forums.cgsociety.org/t/polygons-per-gig/1338279/4 and with 8GB of VRAM should have absolutely no problem dealing with up to 16,000,000 Polygons, is it not optimized?
Thanks for all the Help