Here is a quick mock-up of a build that is overkill. As every second passes, the advancement in technology is taking "huge" chucks of "worth" out of the price/performance from this build. There is no need to over kill this hard, however I know how you feel when it comes to getting bigger and better because you can!!
Over Kill (Power level is over 9000!! )
http://pcpartpicker.com/p/373ed
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Here is a starting place for an overkill but viable build. I hope others can help me tweak if to perfection to suit your wants and needs. When customizing you get to build it exactly how you want it!! There are somethings I assumed but the general build is below.
PCPartPicker part list /
Price breakdown by merchant /
Benchmarks
CPU: Intel Core i7-4930K 3.4GHz 6-Core Processor ($568.99 @ SuperBiiz)
Motherboard: Asus Rampage IV Black Edition EATX LGA2011 Motherboard ($464.99 @ SuperBiiz)
Memory: G.Skill Ripjaws Z Series 64GB (8 x 8GB) DDR3-2133 Memory ($680.98 @ Newegg)
Storage: Samsung 840 EVO 750GB 2.5" Solid State Disk ($349.99 @ Amazon)
Storage: Samsung 840 EVO 750GB 2.5" Solid State Disk ($349.99 @ Amazon)
Video Card: EVGA GeForce GTX 780 Ti 3GB Video Card (2-Way SLI) ($775.91 @ Newegg)
Video Card: EVGA GeForce GTX 780 Ti 3GB Video Card (2-Way SLI) ($775.91 @ Newegg)
Case: Cooler Master Cosmos II (Black) ATX Full Tower Case ($300.98 @ Best Buy)
Power Supply: XFX ProSeries 1050W 80+ Gold Certified Fully-Modular ATX Power Supply ($198.98 @ Newegg)
Optical Drive: LG WH14NS40 Blu-Ray/DVD/CD Writer ($53.99 @ Newegg)
Sound Card: Creative Labs Sound Blaster Zx 24-bit 192 KHz Sound Card ($109.99 @ Newegg)
Other: Custom Liquid Cooling Solution For CPU + GPU + GPU ($800.00)
Total: $5430.70
(Prices include shipping, taxes, and discounts when available.)
(Generated by PCPartPicker 2014-03-09 19:35 EDT-0400)
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Now then lets go through a few questions.
RAM: Would you like 64GB RAM? 8 GB runs games just fine currently but with your budget I would suggest 16GB and only 32GB if you just want to rub it in everyone's face. Any more than that and you are losing value in the system too rapidly over time.
The RAM I selected is 64GB of pure madness and not necessary. It's up to you if you want it.
GPU: I stuck with two of the EVGA 780ti's because yo will be set for 4K resolution gaming for a while with those two. Possibly a third card if someone really thinks it is needed. I will admit that I am not yet savvy with custom liquid cooling but I highly suggest doing so for this build.
I would like someone else to give feedback on what to implement for a liquid cooling solution. I added $800 for the loop in the cost as my estimate for the custom loop cost.
I would like to also note that if you want to be bigger and better than everyone; your best bet would be to upgrade the machine over time. When better parts become available and others are catching up to your monstrosity you should then upgrade and leave them in the dust once again. This is the best way to stay on top and have full bragging rights.
SSD: I am not sure how much room you need for storage but I suggest a large SSD for your operating system as well as all of your games and highly used applications. Typically I would suggest a HDD for the extra storage if you have a lot of other things but I am not sure precisely how much room you require. Also the PCIe SSDs are the fastest on the market however I do not believe they are worth their costs especially for a gaming build.
CASE: Again I do not have enough liquid cooling knowledge to know about which cases are better suited for the loop however I believe this to be a great case for your build. Someone can change this to fit the loop requirements.
PSU: 1050W should be plenty for the estimated 831W draw from the machine. It's a great PSU from a great brand.
I hope others will help edit this to create the machine you are looking for!!