Had the same imac since 2009 and finally got fed up.. first build in at least 15 years with the goal of doing some gaming and minor video/photo editing and it went relatively smoothly. At first I was really out of the loop so I just sorta picked what the masses seemed to like on this site that was somewhat in my price point, then once I had a basic setup I started reading/watching reviews, looking at benchmarks, pricing stuff a little more and learning/changing things as I went.
took some crappy pictures of it all setup, please don't laugh at my cable management but if you have constructive criticism or tips to do it better I'm all ears.
that keyboard actually came on the bottom of that giant box exactly as is in the picture with that huge wad of paper on top.. had to include that as it made me laugh :)
I'll say that I'm really happy with this case when all is said and done first and foremost. I am only using the one SSD as my system drive which is behind the MB, and I have an external HDD for media/files so I pulled out the drive tray altogether so it's full of room for good air flow.
couple things I'm not totally happy with but will likely get over quickly..
the push to release hinged thing on the front panel.. every.. fricking.. time.. I go to move the case at all, I accidentally pop it open on one or both sides. annoying, but not a deal breaker.
the window seems like an actual dust magnet, like, if I dropped tiny bits of sand from waist height about 2 ft away from this thing, I'm almost positive most of the grains will defy gravity and be pulled over to stick to the window!? it's like it's statically charged...
the finish on the front is nice, but seems to mark up really easily.
so far I love these monitors.. the price point was good enough that I could afford two of them, and granted, they're only 1080 resolution, but side by side it's an awesome amount of screen real estate, and I really couldn't care less about 4k at this point so for now I couldn't be more happy with them.
the menu system is pretty good once you figure it out too, not usually a fan, and it's certainly not perfect, but I customized it a bit and now I can do what I need to do pretty quickly.
I'm using hdmi to monitor 1 and dvi to monitor 2 so I can run SLI, and then hdmi on the 2nd one goes to my cable box, which is good enough for my needs, but for anything with a lot of motion like the hockey games I'll watch on it, it's just average. you could probably argue that the compression cable companies use for hd is likely a factor as well though as you wouldn't typically sit 2 ft from your tv screen :)