Okay, my preferred basic gaming system (tower with OS) is here:
http://pcpartpicker.com/user/wildfire707/saved/t8mmP6
It has the following parts:
CPU Intel Core i5-4590 3.3GHz Quad-Core $188.99
Motherboard ASRock Z97 Anniversary ATX LGA1150 $94.98
Memory G.Skill Ripjaws X Series 8GB (2 x 4GB) DDR3-1866 $80.99
Storage Western Digital Caviar Blue 1TB 3.5" 7200RPM $55.98
Video Card EVGA GeForce GTX 760 2GB ACX $233.99
Case Corsair Carbide Series 300R Windowed ATX Mid Tower $79.99
Power Supply EVGA 750W ATX12V / EPS12V $59.99
Optical Drive Lite-On iHAS124-14 DVD/CD Writer $14.99
Operating System Microsoft Windows 8.1 (OEM) (64-bit) $89.98
----------------------------------------------------------------------------------------
Total $899.88 ($45 rebates included and $5 discount included)
Keep in mind that this is not set to overclock, but for another $65 you can get an i5-4690k and a Cooler Master 212 EVO heat sink.
From my perspective, this comes with a good power supply, USB 3 windowed case, decent motherboard, good memory, an upper mid-range video card, good DVD drive, a decent hard drive, and an operating system. My setup does use the stock Intel heat sink/fan combo. Just assemble it and add a keyboard, mouse, monitor, and speakers.
On a final note, this can run all current games at high settings at 1920 x 1080 - but not ultra.