Hi,
 
About 4 years ago I invested in an i7 980X to give me longevity before I upgraded.  I am debating if that time has come or if I should wait a year or so more.  I currently am using two EVGA 780 Ti's and will keep them for a while longer as I game in 1080p (using a 120Hz monitor for either 120 fps or 60 fps in 3D Vision).  I may jump to 4K in the future but want to wait for more options in 4K with G-sync and for more GPU choices with 4+ VRAM.
 
My question is will I see much improvement in the more demanding games today going from a 980X OC'd to 4.1 to either a 5930K or 5960X?  And, if so, which is a better investment with a similar goal of having the CPU for around 4 or so years.  I am leaning towards the 5960X as more cores might give it more longevity, but would the 5930 allow a higher overclocked speed?  I am not sure how long it will be before games really take advantage of 8 cores / 16 threads.
 
For a 1080p setup with a 120 Hz monitor, will I see much benefit in upgrading the CPU at this point?  Or, should I wait another year or so?
 
I welcome some feedback.
 
Thanks.

IF you upgrade the motherboard and cpu, I would highly suggest 4790k or 4690k, on the z97 platform. You will not see much performance gain, but you will see a reduction in power consumption.

As aka_Steve stated, better monitor or gpu would be the best step forward.

It's very hard for someone who want to upgrade 1136 to choose 1150 platform.
If you want to upgrade than better wait next generation, no reason to invest in passing hardware when you have chance to upgrade from
6 to 8 cores
DDR3 to DDR4
Triple Channel to Quad Channel
SATA III to SATA Express + M.2 
USB 3.0 to USB 3.1
 
Than really no reason investing 200-300$ less in something what you have on X58 rev II. 
You will get only 2 cores less and 30% higher speed per core.
Even some premium Z97 combinations are 200$ less than X99.
16 GB DDR4 on 2800MHz C15 cost 215-220$, normal DDR3 16GB is 150$, motherboard premium is 50-70$ cheaper, processor is 50$ cheaper if you want 6 core and 5820K is better than Z97, and you will enter in 2018 with DDR3 platform if you don't want to change on 18-24 months.
Next Intel and AMD generation will be DDR4, no more DDR3 is finished officially.
 
You should know that Windows 10 and DX12 will love more than 4 cores. 

Well said Lehpron.  Only reason why I went with the X99 upgrade was because I got a free MB and Ram. lol  That right there was enough of an excuse to follow through.  

Everyone, thank you for the helpful information.  I did forget to clarify what types of games.  I mostly play singleplayer with an occasional play of Elder Scrolls Online.  With the exception of ESO I don't think really any of the games I am playing now or plan to in the near future are very CPU bound.  ESO does get CPU bound in populated areas but not to a point that it is unplayable with my current setup.  Also, I would not upgrade for ESO alone.  I don't do rendering or video editing so I mainly want performance for gaming.
 
Where I was probably not very clear in my original post is I am trying to determine if my i7 980X and X58 are limiting my dual 780Ti's in non-CPU intensive games (due to it only supporting PCIE 2.0, for example).
 
I don't plan to get a larger monitor or multiple monitors anytime soon as I just don't have space for that.  I believe my next monitor jump would be to 4K, but ideally around 24 inch.  Dell has one such monitor with overall good reviews but no g-sync.  So, I think I will wait till there are more 4K options before jumping into that.
 
I don't think I want to do the Z97 upgrade as while it would be less expensive it does not sound like an upgrade path that would last for 4-5 years.
 
It sounds like for my current interest in gaming I am better off waiting till I am ready to jump into 4K.  By then there will be more GPU options and better hardware across the board.  That is a good thing I think as I will continue to get a good use of my investment in my current build.  Aside from upgrading the CPU cooler, memory and GPUs, the rest is all 4 years old.
 
Thanks again for the advice.

100% disagree with what everyone else has said!    First x99 is a very nice platform and a good successor to x58. 
 
It runs SLI faster than my x58 did.  I was running 4.4 on a 6 core 970 and I went to a 6 core 40 lane x99 at 4.7 and I get about 10 minimum FPS better on heaven benchmark, @ 3x 1080p extreme everything no aa, with the same cards.  The slot layout may be a bit better on the classified as I was coming from an Asus P6t-e or whatever which stacked the two x16 cards.  My new rig just runs graphics better with less frame rate drops,  also could be the 3.0 lanes either way my 2 780 6gb cards are much smoother and put up better numbers than on x58.  Even though i had a highly overclocked i7 970 with 6 cores, (the same cards you have with perhaps more ram) they were unleashed by a good amount on x99 5930k vs x58 6 core @ 4.4 ghz, much smoother performance.  I still love the x58 platform and wish they still made mobos but to answer the question directly you will get higher fps and better min fps on x99 with sli'd 780s.
 
The x99 has a much better storage subsystem. You can pull a lot more bandwidth and real world performance from raided native 6gbps SSDs on the intel chip or go for the new m.2 standard and get something like 4 lanes.
 
I like the classified a lot, the Asus has more voltage controls in the bios which I'd like to see incorporated in the evga bios, but it booted and loaded windows 7 first time up. 
 
I was in a very similar position and looking at the difference between upgrading the cards to 980s or going x99 with a new storage set or running your old gear at native 6gbps on intel you'll notice the x99 is an upgrade that will take the rest of your gear to another level and be an upgrade for several years.  They also have a nice 8 core chip differentiating the X.
 

congrats on the new system! 

Johnnyguru.com has really good reviews on PC PSUs.  Personally I've found you want tight regulation and little to no ripple for high overclocks so if you look at the reviews compare the ripple between the two.  H100i you can push-pull on that will drop about 3-5 degrees. 

I think a common outlet would have 3600 watts depending on the breaker.  but assuming a 30a breaker * 120v is  3600watts and 15a breaker *120v is 1800watts

gtxjackbauer
Two things.  
 
You won't get PCI-E x16 on 3 lanes if you were to get a 3rd GPU.  I believe it would come out as x16, x8, x8.  Correct me if I am wrong.
 
Secondly, the AX1500i is way overkill unless you're doing quad SLI plus, our standard outlets are rated at 1300w max I believe as you'll need to change it to support a full 1500watts.  A 1200w PSU would be ideal if you were to go with a triple GPU SLI setup.

Good points.  Yes, you are correct that with 3-way SLI I would have x16, x8, x8.  That and the fact that I don't think 3 ACX cooled cards would do well stacked next to each other has steered me away from a third GPU for now.  Maybe down the road if I get adventurous and decide to liquid cool the GPUs I will consider a third or fourth card.
 
Well, I already have this AX1500i.  I see now that it was really overkill.  I am torn as to whether I will keep my HX1000 and try to sale this AX1500i or just use it and know that while overkill it will definitely meet my needs.
 
I am just not sure if the AX1500i offers any meaningful benefits over my HX1000 beyond the obvious wattage differences.

From a core i7 980x no its not worth it trust me. Your still going to get a few more years out of your x58 setup and that cpu before you even see a slow down that's noticeable from it. Do not even consider the  4790k or 4690k on the z97 platform, even the z87 platform. You will notice without those threads, any game that takes advantage of multi core cpus, will in fact take longer to load.

well for me i had to build new reg becouse old one was a p4 lol that died. it was 12 years old . so i put wow hunter toghter and as soon as i finish it and the kids ,wife and grandkids saw it they took it over lol so started one for just me a way over the top i'm sure for most overkill to play my game //////// warcraft . wanted to do with 3 monitors so allmost 2 years ago i started buying the parts to do it was going to build a SRX go a new mb but changed to a x99 classified build and wanted it to be all evga that i could do and want it to be biger and way faster than wow hunter so u can look see  what u think of my new build working on is wow hunter2 .