It was unplayable too. Even with 16gb RAM. I gave up trying to play it (just stutter heaven even on a Fury X). A good year or so later I tried it on my Maxwell Titan X and it was OK. Not the greatest game ever, but the graphics were quite pretty and some of the cars sound lovely going through a tunnel !
It's kinda like Fallout 4. They have literally made it better post launch. I remember playing it at 4k on launch on a single Fury X and noticing that the far off backgrounds were covered in this nasty fuzz I hadn't seen in a game in years. I played it through once (dropping to 1440p) and the graphics were just nut sacks. Properly ball bags.
Any way, fast forward to about a month ago and I start my second playthrough as a woman (so I can access all of the girly things like Black Widow perk etc) and the HD pack combined with the HD weapons (Nvidia only IIRC) and etc make the game look absolutely stunning in the situations where you want it to (IE like in FO3 you are walking through some burnt out stick trees and this lovely sunny glow comes through).
And the BG no longer looks like fuzzy ass either, win !