New build now; or wait?

Hello World. I'm in the market for a new build. The last time I built a new machine was a few years ago. My current machine is AMD Based (CPU: AMD Phenom II X6 1100T Processor 3.30 GHz "hexacore" - GPU: AMD Radeon 6990 - RAM: 12gb Corsair I forget the speed). I prefer to run a (3) multi-monitor solution when I can (currently at 1080p). Anyway; that's from whence I came. I think that I’d like my next build to be intel/nvidia based. I’m having a rough time deciding on whether I should wait for this “next gen” stuff to come out from intel & nvidia (i.e. the  X99 & the Nvidia 800 series) This WILL NOT be a budget build (though I don’t intend to buy a Titan Z), but I may spend upwards of $3k; in order to not “have” to make another build for the next few years. So I’m looking for some advice for a high’ish end system with the current generation tech (that’s out now), & also any educated speculations in regard to whether it would make more sense to wait for the “new stuff”, & what those pairings might be. Thanks in advance for any info.

F.Y.I.

Here are some of the current generation items I was looking at if I were to upgrade “sooner than later”.

GPU: EVGA 03G-P4-2888-KR GeForce GTX 780 Ti Dual Classified w/ EVGA ACX Cooler 3GB 384-bit GDDR5 PCI Express 3.0 SLI Support Video 

MOBO: ASUS MAXIMUS VII HERO LGA 1150 Intel Z97 HDMI SATA 6Gb/s USB 3.0 ATX Intel Motherboard

CPU (when it’s released after 6/25: Intel Core i7-4790K Haswell 4.0GHz LGA 1150 Desktop Processor BX80646I74790K

RAM: Mushkin Enhanced Redline 16GB (2 x 8GB) 240-Pin DDR3 SDRAM DDR3 2133 (PC3 17000) Desktop MemoryModel 997170R

Well the 6990 is still a pretty good GPU assuming you don't have many problems with it. You could upgrade to X99 with a 6- or 8-core Intel CPU and keep using the 6990 until nVidia releases they're top-end GTX 800 series card and pick up two of those. Assuming the trend of the Titan-z continues, you'd probably want to buy two individual cards instead of a dual GPU card.

But seriously, assess the performance of your current setup. If you're happy with what you have, you could just keep waiting until you're not and then upgrade.

I want to stay away from Dual GPU cards (I didn't really experience much benefit from the 6990 when I upgraded from two (X-fired) 5870's the last time I upgraded. I'd like to get the top of the line Single GPU. Though your thoughts about upgrading to X99 (when it becomes available) and waiting for the Nvidia top-end cards to release sounds pretty good. Do you think it's possible that my current MOBO/CPU configuration could be "bottlenecking" my radeon 6990 GPU?

current MOBO: (purchased mid 2010)

Asus M4A88TD-V EVO USB3 Motherboard - AMD 880GX, Socket AM3, ATX, DDR3, USB 3.0, RAID, SATA 6.0GB/s

current CPU: (purchased early 2011)

AMD HDE00ZFBGRBOX Phenom II X6 1100T Black Edition Processor - Six Core, 6MB L3 Cache, 3MB L2 Cache, 3.30GHz, Socket AM3, 125W

Another thought; if I'm primarily gaming will I really get a large benefit buy waiting for the X99 MOBO's & CPU's to come out; or is the Z97 with an i7-4790K (after it's released) plently? I only ask because I hear that most games don't even take advantage of a quad core CPU.

I'd wait until the new 800 series is released from Nvidia. And maybe the X99 stuff from Intel. If you grabbed 2 of the top end 800 cards you'd definitely not have to upgrade for years. A single one of those cards should destroy games for years to come, and 2 should keep you playing bleeding edge games on max (or very close to max) settings for 3 or more years. 

X99 should be amazing. If you pick up one of the 6 or 8 cores, and over clock, then you should have a true monster of a system with the 800 cards.