ADVICE NEEDED

Yesterday I picked up a small server tower with an i3-6100 , 20gb ram, and 2 3tb hard drives. I want to run unraid with a plex server on it to (legally) watch movies and tv while also storing some of my families pictures.

Currently I plan to buy another 3tb hard drive to have a true array. 32gb of ram. Should I get a low power gpu like a rx580?