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I think the Maximus VII Hero is a fine choice.
And the i7-4790K is absolutely the best and fastest Intel CPU a gamer could get (until Q2/2016, anyways, lol). If you're not planning on overclocking, the "non-K" i7-4790 is a little cheaper, also a little slower so not as popular.
A Titan X is a whole lot of GPU. You can get
essentially identical raw fps/performance (for most games and most other things) from a 980Ti for substantially lower cost. A Titan X requires at least 16GB of main RAM for optimum operation.
Best to choose RAM which is
QVL-tested for your mobo. Realistically, you could get by well enough with 8GB total RAM but it'll slow some things (and some gaming) down a bit, 16GB doesn't cost too much more but is much better (for heavy games) overall, while 32GB or more is basically an overkill waste of money (for gaming) unless you plan to load it up with the Asus RAMDisk software. It's best to buy a single 4x4GB or 2x8GB dual-channel DDR3 kit and avoid mixing and matching multiple (even identical) kits. Your mobo claims to support up to DDR3-3200 (with an epic-overclocked processor part, anyways), but I think DDR3-1866/2133/2400 is more realistic and costs less and has faster timings/latencies significant enough to make a little difference in real-world (and gaming) performance, why pay more for big speed increases you probably can't make any use of, and why not pay less for little speed increases you can?
This G.Skill kit seems like a fine choice. Corsair memory is overwhelmingly popular and actually tends to be very good, but I think it's priced far too high when there's faster alternatives to choose from.
You could probably get buy with a 750W PSU, but that phat GPU might be happier with 900W+. I wouldn't personally buy a Corsair PSU, seen them fail too often and been underspec too often to trust themis as a PSU brand. This
Rosewill Photon 850W Gold PSU is currently a great deal, an EVGA SuperNova 900W+ Gold/Platinum PSU (with its unbeatable 10-year warranty) would be even better, if/when you can find one on sale.
The PC case/chassis is basically a personal preference. I prefer understated, sleek, elegant cases (like my Obsidian 750D). Other people prefer garish and aggressively-sculpted gaming beasts. Most gamers want pretty windows which showcase astonishing LED arrays, I prefer a solid metal box which offers "proper" EM shielding. Anything which fits your motherboard/PSU form factors and CPU cooler and GPU card length which has sufficient drive bays will do. Cooler Master HAFs (with their inevitable military-themed mods) and Cosmos Cruisers (with their inevitable automotive-themed mods) seem very popular at local LAN events. If you genuinely don't care then just pick up whatever's on sale - chances are if the inside is painted black then it's got all the other "enthusiast-grade" amenities like rubber grommets and semi-modular drive bays and little anchor points and cable channels and extra-sized cutouts and all the rest. "Tool less" means "convenient" but, to me, also tends to mean cheap plastic screws and parts instead of nice durable metal ones.
All-In-One (AIO) or Closed-Loop-Cooler (CLC) is the same thing, and the Corsair h100i (or it's beefier siblings) is probably the most popular cooler you'll see in gaming rigs these days. There are quite a few (non-Corsair) AIO options which are better, in my opinion. If you don't want to worry about the (largely exaggerated but still not-impossible) risk of liquid spilling onto your CPU/mobo then go for a large-air cooler - but you'd need a truly massive beast like the Noctua NH-D15 to get comparable cooling efficiency. The only things better are custom watercooling - which is a rewarding but very involved pastime - and exotic subzero cooling (phase-change refrigeration, TECs, LN2, etc) - which is best left, IMO, to crazy extremists willing to burn money for record-breaking overclocks, lol.
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