The lowest minimum I'd suggest is an i5 4440 if you're on a budget, otherwise i5 4670K or higher to ensure every game runs well. With AMD some games do not run well and you end up having to jump through hoops to make them work well, Planetside 2 ran like crap for the year and half until SOE got around to optimizing it for AMD, the majority of MMO games are single-threaded where AMD loses out on single-threaded performance, a few FPS/action games are multithreaded (Half-Life 2, Battlefield 4, etc.).