not sure what i'm doing wrong

so i finally got all the parts in to build the crusher and finally got it to run! i was super exited. i downloaded all the drivers and got windows 10 installed. Finally time to play some Over Watch!!! (i thought)

i booted up the game and everything looked alright, but the game ran at like 12fps :( so i tinkered with the settings and the only real way to get a steady 30fps was to set everything at the lowest setting and turn a bunch of stuff off... i feel like i'm doing something wrong. from the description on the wiki, this thing should handle over watch like a champ at medium to high settings with 60fps, at least that was my understanding.

this is my first build, so i'm honestly clueless of what is going on. if anyone could give me some guidance as to where i could maybe start to solve the problem (if there actually is one) i'd really appreciate it!