You don't need a gaming PC, bro. (unless your PC is already slow.) I have an average, run-of-the-mill PC, and I have
Warframe,
The Sims 3,
The Sims Medieval,
Most of the remotely good MDickie games,
Minecraft,
Skyrim,
Oblivion,
Sumotori,
Toribash,
The Great Big War Game,
Some old corny kids' rpgs like W101 that my little cousin insists I play with him,
Project 64, on which I have Mario, and both of the N64 Zelda games,
TF2,
Starmade,
Facade,
The Chzo Mythos,
The Trials of Odysseus Kent,
Some other odds and ends.
Along with this, I have several other programs characteristic of your standard office PC for my homework, and various programs that are the tools of my picture-pasting forum-lurking trade. All of these games I have run with reasonable graphic settings, (as in, not having to turn everything down to 0, and my framerate usually can afford some additional improvements if something looks like crap) at very nice speeds. And I'm using a 3 year old Toshiba laptop.