For the processor, I have chosen out the i3-6100 from Intel. Intel's recent Skylake entry has excellent single-core performance for gaming, and supports DDR4. If you need extra physical cores, go with an i5 or a similarly priced option from AMD.
Some games will still be benefited from having more than two physical cores, namely AAA games such as GTA V. So, if you have the money, go for an i5. However, AMD's options at the i3's price point are worse than the i3, which means you should either buy an i3 or an i5.
The motherboard isn't anything special, but it is a very good unit from Gigabyte. While it may be cheap, it has all the features we need.
This 2x4GB kit from G.Skill is a great DDR4 kit clocked at 2400 mhz. You can choose to go with a single 8gb stick if you want to upgrade to 16gb later, but honestly a gaming build of this caliber won't ever really need more than 8gb of RAM, so there's little point in upgrading. In case you don't already know, 2x4GB of RAM is basically faster than 1x8GB.
A basic 1TB hard drive. Enough space for all of your games. If you want ULTRA FAST BOOT TIMES, buy a 120GB SSD for your OS. The Adata SP550 and the PNY CS1311 are two excellent budget SSDs. Stay away from the SSD Now V300 series please!!!
This hard drive is perfectly fine for gaming. If you think that this drive will fail after a few months when a WD Blue woudn't, you're wrong. Both are perfectly fine options for 1TB hard drives, it just so happens that the Barracuda is cheaper.
Also note that if you are buying an SSD, make sure to install your OS onto it.
For the graphics card, I went with the R9 380 4GB. I had to fight the urge and not return to one of my favorite graphics cards at the moment, the GTX 960, because while it usually runs cooler, and I love how I can seriously overclock it without even having to turn its fans on, the R9 380 has better raw performance, and performs better in a number of games. The extra 4GB of VRAM will cover future titles (and current titles that use a lot of VRAM, such as GTA V. Since this PC can play games like TF2 and LoL at 4K easily, it will also help cover a few other 4K needs.
AMD cards are no less reliable than Nvidia cards for the most part.
The case is pretty basic, fairly small, decent airflow, USB 3.0. If you want a really good looking case, spend the extra money for an NZXT S340.
This Seasonic 80+ Bronze unit is very popular and is very reliable. This PSU is a great choice for anyone building their first PC, or for an experienced builder. All in all, the power supply here was an easy choice.
Since it isn't worth it to make a $650 build guide, I'll list potential upgrades here. Your first option would be to get an SSD and replace the R9 380 with an R9 380X. The other option would be to go with an i5-6500 or 6600 instead of the i3. You could also choose to put your money entirely in storage, and get an SSD and a larger capacity hybrid drive.
Blu-ray/Optical Drive - Get this if you really need it. Wifi adapter - Get this if you need it. Use ethernet whenever you can. Case fans - Get these if you really want better cooling.
Most people have a mouse, keyboard, and a pair of ear buds. Those will suffice for gaming. Gaming grade peripherals don't always mean that much, but if I were to suggest stuff, get a G710+ keyboard and a Steelseries mouse. If you want headphones, buy a cheap pair from Sennheiser, and if you want a headset, buy one from Logitech or get that super sweet Kingston Cloud II. I don't include the OS because usually you will have some way to get Windows for free, or you won't even want to use Windows.
Star Wars Battlefront (Ultra 1080p): 60-70 FPS
Fallout 4 (Ultra 1080p): 50-60 FPS
GTA V (Ultra 1080p): 50-60 FPS
|Intel - Core i3-6100 3.7 GHz Dual-Core Processor||6W - 51W|
|G.Skill - Ripjaws V Series 8 GB (2 x 4 GB) DDR4-2400 Memory||5W - 5W|
|Seagate - Barracuda 1 TB 3.5" 7200RPM Internal Hard Drive||4W - 20W|
|XFX - Radeon R9 380 4 GB Double Dissipation Video Card||47W - 190W|
|Total:||62W - 266W|