Comparing gaming computers

Solution
The prebuilt has an i7 and 16gb RAM. For gaming the computer would be ideal with an i5 and 8gb RAM as it will perform the same for less money.

Your list has a rendering and encoding CPU. This is a HUGE waste for gaming. Change to an i5 4690k and a z97 motherboard. It also needs a 650w PSU. You will NEED a HDD in addition to the SSD.
The prebuilt has an i7 and 16gb RAM. For gaming the computer would be ideal with an i5 and 8gb RAM as it will perform the same for less money.

Your list has a rendering and encoding CPU. This is a HUGE waste for gaming. Change to an i5 4690k and a z97 motherboard. It also needs a 650w PSU. You will NEED a HDD in addition to the SSD.
 
Solution
I don't really have the time. Just change the few simple things I told you.

Get a 650w PSU from Antec, XFX, Seasonic.
Get an i5 4690k
Get a z97 motherboard. A decent one (somewhere in the middle of the price range) as it looks like you will be doing some heavy overclocking.