2x 980's to get close to 4k as possible.

I fully plan to go SLI, but for the build let's just stick with one 4GB 980. Once 6GB and 8GB 980's hit the floor, I'll be swapping out the single 4GB card anyway. This essentially will be a 2-stage build.

I've reworked my original post and intention description.

Liquid Cooler
- XSPC Liquid Cooling Specific ?
- Cooler Master Nepton 280XL Aluminum Radiator Dual 144mm Fan Rifle Bearing CPU Water Cooling Kit ?

I'm leaning towards Cooler Master Nepton 280XL, but again I have never attempted liquid cooling before.

For today, my attention is on websearching audio capture devices.

Audio capture (mic) professional level
- ?

Video capture (professional level)
- ?

Finally, how might I incorporate Thunderbolt 2.0 into this rig?

You might want to plan for a 2-SLI Titan X or 3-SLI 980 setup, I think, that's a lot of resolution. And I hate to say this here - but you might want to look at the MSI X99 Gaming mobos for this build, I understand they include some dedicated on-board streaming hardware (for live gameplay broadcasts and such) which might be useful for your purposes.

Fully plan on an SLI setup, in the future.

I've compared Asus x99 (rampage extreme) to MSI's x99 mobos. They don't seem to have any edge over Asus for my purposes. But I'll keep comparing. Plus I have no intention of live-play streaming. Just recording to local disk while playing onine. I plan to record and produce edited content. Not twitch stuff.

https://gaming.msi.com/products/motherboard/x99-series
http://www.asus.com/Motherboards/RAMPAGE_V_EXTREMEU31/

I'm telling you, you need SLI NOW.

The i7-5960x is a cool toy which will not net you any more real world performance, and just cost you an extra $600 on useless crap which could have been spent on useful components.

2x980s or 3x290xs as a minmum for 4k gaming. Otherwise there won't be a single modern game you can play at 4k on even medium settings and get a consistent 60fps.

Think of it like this: 5960x and one 980 is a Porsche GT3, 5820k and two 980s is a custom-built bigtire, top-of-the-line dragster. Both would cost you the same, both would be really nice cars. But your goal isn't to finish the nurburgring, it's to finish the quarter mile in 5 seconds or less. The custom bigtire will provide you a lot more, since it has a larger tire, and way, way more horsepower and torque.

I guess it's ultimately your choice.

Again, I would not recommend hardware based capture but software based. Camtasia is a recording and editing suite, for $150. Amazing piece of software, many very big youtubers have attested to the quality. I would not use FRAPS for recording. It takes beautiful screenshots, but the recording feature is poorly programmed and prone to crashing, and unless you're on a tight budget (which you're clearly not) is better to say away from.

If you want a great microphone, look no further than the Blue Yeti. Make sure to buy the pop filter as well.