i don't know how well of a computer you can get for $500
500$ is good enough for 1080p 60fps on medium-high settings.
That's a pretty useless measure without saying which game they can expect to run at that level
Battlefield and GTA V
http://pcpartpicker.com/guide/nVG323/grand-theft-auto-v-ready-pc
However if you're actually trying to prioritize on loading games at high speed
the cpu will bottleneck the stuff out of the gpu.
Hardly, the Skylake line is pretty damn fast. The i3 6100 on that list is a dual core with four threads at 3.7 GHz, and the architecture is great on it. It's not the best and may struggle on large-scale things like huge Total War battles but for $500 it'll do.