Both of them are nearly the same, I'd go for the AMD A8. AMD A8 has more cores, also has a better GPU to go with.
I'm not sure if it makes it any cheaper, but im certainly sure paying more for the either isn't worth it.
More cores and a better GPU gives him more options and support on games, he would have a okay FPS playing any of those two games.
Hope it helped,
Greetings