As a college student with a tight budget, I decided to begin a search for the best pc I could build for $300 or less. I took to Craigslist, eBay, and local computer tech shops for any bargains I could find. I figured the best place to start would be to look at the games I play. CSGO, DiRT Rally, Skyrim, Rocket League, Witcher 3, Arma 3. Playing these on my Asus X550 (pictured next to my monitor) was okay but the bottom of the laptop would get so hot and only produced slow frame rates at low resolution. I didn't need a crazy watercooled setup and didn't want to go the Intel route as it looked much more expensive. I realize the psu is a lot more than my machine draws but it will allow me to have ample power for an upgrade and was cheaper than lower wattage power supplies from similar brands. I am gathering as many screenshots currently to prove these prices are real and not just made up to look good. The entire build took about three weeks from start to finish and likely costed at least $30 in gas for meet ups and eBay shipping costs. Note: pictures were taken prior to installing both the Evo 212 and additional 8gb of ram along with an adapter to connect the usb 3.0 hub to the 2.0 on the mobo.
Cpu - $60 eBay (new in box)
Cooler - $20 Newegg (refurbished, like new)
MoBo - $20 Craigslist (open box)
Gpu - $90 Craigslist (used with box)
Ram - $30ish CL&eBay (used)
Psu - $30 local shop (used)
Hdd - $15 Craiglist (used and wiped clean)
Case - $20 local shop (new aside from scatches inside, came with  120mm fans)
Total without OS: $285
OS - $60 eBay (would have gotten 7 and upgraded but didn't complete build in time)
Total including OS: $345
UPDATE 08/14/2016: I forgot to mention this but with the eBay copy of Windows, some work has to be done if you would like it to run right. It is a legit sealed copy but it looks to be from the UK as I couldn't change this setting on initial install. I don't see any real issues but found it just a bit odd. Second, the OS is up to date as of November 2015 which means after install, there will be countless updates and restarts. I also followed Brian's guide from Tech YES City to fully optimize it. That said, for about $60 it's a ton better than paying full price straight from Microsoft but it took me about a night to get everything fully working and running the way it's supposed to.
UPDATE 08/16/2016: I've added pictures of my finished build including the 212 EVO cooler and the additional sticks of ram. System is still performing great reaching at least 60 fps in every game I've game I've thrown at it. Building a rig from used parts has proved to be an awesome route and I highly recommend it. Even better deals can be found on r/hardwareswap but I didn't use this as I don't go on Reddit all that much. Happy building and game on!
UPDATE 08/20/2016: I've slightly overclocked the 6300 to 3.8ghz from the stock 3.5ghz. This has given a slight boost in performance but has caused the motherboard to heat up by about 10°C. I don't really want to push this PC any further given the motherboard just isn't made for this type of strain or heat. For all the games I have it has run them great and without issue.
UPDATE 09/17/2016: I've looked at watercooling my cpu to overclock it slightly more but came to the conclusion that my motherboard isn't outfitted with proper heatsinks, nor proper power phasing. I'd like to upgrade to a 970 gaming mobo eventually but this shall do for now and is still running strong.
UPDATE 10/27/2016: As just a little update, the pc is still running very well being used extensively for 6-10 hours a day with the GPU at near full load. No overheating, crashes, etc. Took some new pictures of some cable management. Since I'm only using my HDD, all the slots underneath were being wasted. I cut a small piece of steel, painted it black to match the case, and drilled the old rivets out holding the HDD cage in. I riveted the new piece in and effectively created a small "basement" to hide excess cables in.