8 gigs of ram has become the modern standard for pc gaming, you should be able to play but with what quality I’m unsure of. Buy some used ram off eBay, odds of getting dead ram are extremely unlikely and it’s cheap, most like G.Skill cover theirs with a lifetime warranty regardless of owner. Ark is however a GPU demanding game, it will bare most of the weight. Expect to see 1080’s at max around 60-80Fps.