Just order one online to be delivered to you and do NOT get a GTX 650 if you want to play this generation of games.
I only have one on my shelf to test for problems if I ever have a graphics card fault. The GTX 650 could hardly play battlefield 3 back in the day
I have no idea what you mean by GPU socket as socket are what CPU's sit in.
GPU's sit in PCI Express slots
You will need a t least a GTX 770 with a 500w round about PSU, GTX 970 is recommended if you want to play this years game and the next.
Also you will NEED 8GB of RAM be it one stick or 2x4GB sticks as that has been the standard for games for a few years now.
Then a quad core 3.0Ghz+ CPU like an i5 4460 or AMD equivalent if you want a smooth gaming experience.