This is the 4th iteration of my personal PC since 2001. I used to play a lot of video games on my PC back in college (Command and Conquer series like Red Alert 2, Yuri's Revenge, Renegade and Counter-Strike). After college I was bogged down in graduate school and didn't play nearly as much as I used to and the C&C series was dying out (wasn't a big fan of Generals). Fast-forward to this year. With Renegade-X being released, I realized THX III wasn't strong enough to play the game and figured it had been five years so it was time for THX IV. I've been pretty good with computers, but this is actually the first one I put together myself.
CASE: Cable management was critical for me. I didn't want to mess around with liquid cooling, but I wanted the option, so I wanted a case that wasn't too small, but also not enormous. I also wanted the air flow to be all in one direction - no crisscrossed fans. The NZXT seemed to fit the perfect balance between air cooling / noise. The Silverstone FT04 was also a strong candidate since it seemed to cool very efficiently, however it was also pretty loud and the build quality didn't fit the price. I figured I could get this case and put the AP Silverstone fans if I ever wanted to cool it even better. The case was by far the hardest decision, because the reviews of cases are sparse and hard to get objective data for. Anandtech does probably the best job.
CPU and heatsink: I was debating between the 4670 and the 4770 - the debate was really about whether I really needed hyperthreading or not. I use photoshop a fair amount and have done video editing once in a while, so I thought it wouldn't be bad to have, but the main thing to push me to get the 4770 was Microcenter had a price drop to $250. That pretty much sealed it. I heard that the 4770's temperatures varied from chip to chip and since my old chip (i7 950) was running really hot, I was debating whether to get an aftermarket heatsink or just keep the stock. I knew I wanted to overclock down the road, but wasn't sure when so I was leaning toward stock. However the more I read about the Noctua NH-U14S and all the tests from various sites - it seemed to be the gold standard as far as heat sinks. It even outperformed a few low end liquid cooling systems and it's quiet as a mouse.
Motherboard: This is probably the one area I probably should have done more research on. I admit I was a little intrigued about having a thunderbolt output built-in and it kinda sold me. I should have maybe just bought the lower end board and saved $60 and if I ever needed thunderbolt, just bought the PCI. Oh, well. It's a good board though. I did have an issue with the computer turning itself on after a shutdown. After a little research, it seemed that on some of these Asus boards people have been having the same problem. Easy fix though, just enable ErP in the BIOS and it fixes the problem.
RAM: 32GB seemed like overkill, even though I tend to have a bunch of browsers, tabs, programs open at the same time. I got a really good deal for the RAM. Since the chip only supports 1600, didn't seem to make much sense to get anything faster. Plus this had pretty good latency.
Hard Drives: I actually bought this Evo 840 a few months ago (I know, I know a big no no to buy parts at odd intervals). But it was a lightning deal on Amazon and I got it for $400. Couldn't beat that price. The other two hard drives are transplants from THX III, so I didn't spend additional money there.
Video Card: I used Tom's Hardware guide for GPUs and this seemed like the best bet for my budget. I knew I wasn't going to be going crazy with the video games to SLI right now, so the 770 seemed right. Plus I have the option down the road, if I really want to.
Power: So this is what everyone seemed to say NOT to skimp on during the build and I wanted clean, reliable power and the AX series by Corsair seemed to be one of the best.
Misc: I haven't bought the Silverstone fans yet, that's kind of on my possibly to-do list. I had the case fans connected directly to the motherboard instead of the control panel on the case itself - I did this because Asus motherboards (like others as well, I'm sure) have a mechanism to control the speed of the fans depending on the temperatures of the CPU and the motherboard itself. So when I started it up, the BIOS kept giving me an error that the fans were running too slowly - the reason they were running so slow was that it was so cool inside the case, it didn't need to spin any faster than 350-450 RPM. I went into the BIOS and told it not to warn me about the fans again unless they dip below 300 RPM, because the default is 500 RPM. Thanks for checking it out!