EDITED - March 20, 2015.
So last year, I built my first custom PC. The purpose of the build was for animation, gaming, music, and video editing, in that order. Over the last 10ish months, I've been trying to learn and inform myself more about how these things work, plus the process of building has been a bit addictive. So I've added a few more things to my build, and now I can honestly say that I'm completely done adding stuff to it, and that this will be my build for the forseeable future. :)
Below, I want to give a bit of rationale to my part selections in case any questions arise.
CPU: At the time I started buying parts, this was one of the better processors available. It was also one sale, and I knew I wanted an i7 for my purposes.
CPU Cooler: This was a new addition. I ran with the stock fan, which did great, but I wanted to have a cooler so that I could overclock at some point.
Motherboard: This was also on sale at the time of purchase, and the price, plus the amount of USB 3.0 ports and PCI slots I could use made it a winner.
Memory: Initially I went with 8 gigs of RAM, but after seeing how much After Effects and Premiere started using, I decided to get a second 2x4GB kit. The second kit was also on sale at the time, which influenced my decision.
Storage: I went with a 500GB SSD initially, and after about 9ish months, I was starting to run out of room. Making the shift from HDD to SSD was amazing, and I couldn't see myself going back, so I saw a sale for a 1TB SSD and took it. The plan was to use the old 500GB SSD for a Hackintosh drive, but I changed my mind, and instead I'm going to use it to house my Steam library.
Video Card(s): I'm sure this will probably bring the most questions. When the build was first made, I was using the 760 as my single GPU. It was my gaming card, as well as the card I was using for CUDA acceleration for After Effects raytrace rendering. I was curious about gaming at 4K, and when the 980 and 970 came out, they both piqued my interest. I was really down to get a 980, but the 970 def seemed to be the better value. I waited for a few months, hoping the rumored 8GB card would drop, but when I saw that production delays were pushing theme back, I happened to see the FTW+ on NewEgg one day and made the plunge.
Once I got my 970, I was thrilled with the performance gains I was getting gaming wise, but I failed to consider something very important in regards to using it as a rendering card. Since NVidia switched from its Kepler to the Maxwell architexture, the CUDA support for ray tracing was no longer a thing. Was kind of disappointed, because I was hoping to sell the 760 to recoup some of the money spent, but in the end, I ended up making the 970 my primary card, and the 760 my card that's being used solely for rendering. Same manufactuer, so no issues (so far).
Case: My very first custom PC that I had wasn't put together by me, but the person did help me select parts and we went with an Antec 300. I was pleased with it; it wasn't too flashy, and I liked the big blower fan on the top. So When I decided to build my own, I stuck with Antec, buying the 900 case. It was on sale, and I thought the blue LEDs were cool. If I build another PC, I may go with a different case, only because cable management isn't the most fun thing to do with this case, as you can probably tell in the photos.
Power Supply: Went with an 850W initally because I knew I'd be upgrading in the near future, and I knew it'd have enough headroom for everything.
Optical Drive: Was on sale, plus, I was thinking a little future-proofing with a BluRay burner wouldn't hurt.
Wireless Network Adapter: I had a StarTech card initially, and I didn't really like it. Plus, at some point, I was thinking Hackintosh, and I knew this was compatible.
Monitor(s): Initially I had the LG Ultrawide as my primary display. Great monitor, beautiful colors, etc. But when 4K gaming started to interest me, I started looking. I still wasn't going to take the plunge because they seemed a bit expensive. But then Black Friday happened. So now I have the 4K monitor to game on, and the Ultrawide to edit video on, and well as do any color work.
Keyboard and Mouse: I just want wireless backlit stuff.
So that's the rundown on my rig selection. I should mention is that I haven't overclocked this yet (I know, I know). It runs everything that I like to play at max without breaking a sweat, so I can't justify adding more heat and power draw to my PC yet. But maybe in a few years.
Let me know what you all think, or if you have any questions, comments, or concerns. I appreciate all the comments already, and I enjoy reading the forums and gathering ideas on making my own stuff better, so I just want to say a thank you to this community. You guys rocks!