Just some random, maybe better, ideas for a cheap gaming PC...
http://pcbuildsonabudget.com/best-gaming-pc-build-under-500-dollars-2016
http://pcgamehaven.com/best-cheap-gaming-pc-build-for-under-500/
http://levelupyourgear.com/best-gaming-pc-build-under-500-dollars-cheap-budget
Those were $500, now for the next level of $600...
http://pcbuildsonabudget.com/best-gaming-computer-for-600-dollars-2016
https://www.youtube.com/watch?v=9hFjWzzAXhg
https://www.youtube.com/watch?v=qIrOJYV7VNI
http://pcgamehaven.com/best-gaming-pc-build-under-600/
But, I would also suggest these guidelines, from personal experiences. You will need to save money for this:
CPU, go for Intel i7 series, get the associated socket type motherboard.
GPU, go for Nvidia 900 series, leaning more towards 960 or higher. I chose GTX 980, so I'm good for a lot of years from now.
RAM, should install 16GB total, for minimum. You'll actually want to do more, but you will be happier you went with 16 instead of 8.
PSU, good namebrand like Corsair or CoolerMaster, 750W minimum. I myself went with a CM Gold 1200W (Silence is Golden) series.
Hard drive, go for a Samsung SSD 850 Pro series, for at least your boot drive. You'll never regret that, and would never want to go back to standard HDD after this.
O/S, go for Windows 10 - very good operating system.
Those were just main concerns I had, as it sucks to build a really low-end computer that will barely run operating system, browser games, and email.
Paul