bicycle_repair_man :
If GTA V makes it the PC, and it's a big "if", I'd imagine that an i5 and HD 77xx would be the minimum requirement.
GTA V is a last gen console game, and will come with specs to match. Any old quad core, and anything over a 8800gtx will do.
Of course you have your Rockstar incompetency when it comes to anythnig pc related to consider.