I'd say if your plan is to stay with the X79 platform, either keep your 3820 or go to a IB-e chip rather than another SB-e.  Personally, since you have a good OC'ing 3820, I would save the money until it's time to upgrade to another platform and keep the 3820.
 
And yes, you'd have to go to IB-e to have native Gen3 support.

Can you find some cheaper version of i7-3960X.
On your place I would sold your setup and upgrade on X99 some budget build.
Now is possible to find i7-5820K and 16GB of memory and good motherboard for around 600$.
Memory is 100$, board around 220-250$ and CPU 300$.
For you setup you can get few hundreds. 
Because i7-5820K is 4960X only with DDR4 and 28 lanes not 40. 
If not on stock clock than on 4.0GHz. Other specifications are same.
And off course new boards arrive with USB 3.1, M.2 and SATA Express support.
 
 
 

If you had 400$ you should sell X79 Dark for 200$ and i7-3820 for 150-200$
That's around 700-750$ in pocket. Even if you get 150+150$ you could make good combination.
 
i7-5820K (320$)+ X99 Classified(300$) + 16GB 2800 DDR4(100$)
That's deal, same performance as i7-4960X, board ready for 3way SLI and nothing special but OK speed DDR4.
It's possible to find and boards capable for 3 way SLI and for 220$... If 28 lanes make you problem Microcenter sell 5930K for 399$.
That mean cheaper board and few more dollars and you could reach that easy. MSI X99 SLI PLUS capable on 3 Way SLI cost 199$.
 

Thanks guys. The only problem with the total system upgrade would be I would have to take my system down and wait until I sold the parts before upgrading. Otherwise the wife wouldn't understand if I dipped into our savings to fix a computer that wasn't broken.   

His best option was to sell X79 Dark 150$ fast, to sell i7-3820 150$ fast... And with that money he have to cover GSkill 2800 DDR4 4x4 GB and MSI X99 SLI PLUS on Newegg. Together they cost exactly 300$. He explain that he saw i7-3960X for around 400$ and probably have 300-350$ saved. He could save 50$ more and to choose between i7-5820K and i7-5930K from Microcenter for 399$ new with 3 years warranty. That's build for 3-4 years. i7-3820 and i7-4820K are not weak processors but because new platform with newer memory, USB 3.1, M.2, SATA Express, etc... together that is not so good option any more as before DDR4 show up. 
That was best possible combination, you can think two days, better combination than this is not possible to find.
He have 3 graphic cards, I would sacrifice and one graphic card if need and go on even cheaper board and for 149$ X99 Micro 2 is enough for SLI.
Only to cross on newer platform as soon as possible. 

MhzManiac
So while I'm waiting on parts, I have a question:
 
Why do people buy high speed ram like 2100 or 2400 speed for an X79 platform when most socket 2011 memory controllers on I7 cpu's only support DDR3 1333/1600/1866 according to Intel's 3820,3830,4820 and 4860 specs? I see people complain all the time and it kills me.

My rule of thumb has been to buy one speed ram above what Intel says the CPU supports.  So for example if the CPU supports 1600MHz max, I buy 1866MHz.  That way it pretty much guarantee's that even with a medicore memory controller, it should work fine.  At least it's always worked well for me that way...

So parts are in. I've only tried the 760 SC first to see what it brings to the table in 3 way SLI. I must say I hate the way you are forced to use 16x8x8x. If I place them 16x16x8x none of the bridges will reach. I'm using 40 pcies lanes in that config.. There is a post on here where a member did this with crossfire MSI cards, so I figure I can do it as well with the right parts.
 
In standard 3 way I saw Vantage go from 44200 to 45860. This is not a bad score but not acceptable as I know I can do better. So I ordered a 7" long Asus flexible  3 way bridge from Amazon last night; hopefully that will work. It arrives Tuesday so this portion of the upgrade is on hold. I will install the new cpu tonight and see how far I can push it.

 
So out of the gate 4.65 at 9-9-9-32 is the best it will do. It will need some baking in to get higher. 
I'll keep trying each day for progress, but for a used chip at least it works.
It took me almost a year to get my sandy from 4.3G to 5G. Only time will tell.
 
 
 
 

Thanks. So it booted up so nicely this morning, I decided to bump up to 38X. It booted into Windows first try. 
Runs cooler even with almost as much voltage as I used on the Sandy.
 
 

Nice OC on your new 4820...

MhzManiac
Thanks again bdary. I'm trying for 48X and it's almost there but it needs some more bake in period. It's almost into Windows and restarts; Adding voltage does not help. I will try again soon. 47X is rock steady though. 
 

You're welcome.
 
One thing you could try if you haven't yet is enabling the "kboost" feature in the BIOS.  I remember when the Dark first came out that that feature seemed to have helped with higher OC's on the IB-e chips moreso than the SB-e.  It gives a split second boost of vcore voltage at bootup.
 
You could also try going up a bit slower by using the BCLK Frequency setting.  Leaving the BCLK Freq Ratio at x1.00, just up the Freq setting to 101 to start.  This will net you about 4.745GHz.  Then 102 would be about 4.790GHz, etc...
 
I also recall reading that the IB-e chips didn't OC quite as high as the SB-e chips so you may have reached it's limit without a lot more voltage.  But that could just be on a chip by chip basis?  Even if that's the case here, 4.7GHz is a real nice OC on your 4820...
 
Keep us posted...

Well the connector arrived and is installed. I got 3-way 16x-16X-8x SLI. 
 
Ran Vantage with all default settings and got the highest score ever for me. Says higher than 99% of scores submitted.
 
Check it out.

Just ran it again after letting the system settle down and almost hit 50K. (49666)

MhzManiac
Just ran it again after letting the system settle down and almost hit 50K. (49666)

 
Great job!

MhzManiac
Just ran it again after letting the system settle down and almost hit 50K. (49666)

You beat my Vantage GPU score by 5.9%! (980 Ti) - http://www.3dmark.com/compare/3dmv/5376065/3dmv/5375522 
 
Is your GPU utilization less than 50% in the first test, and less than 50 % during some of the others?