can an i7 950 oc'd at 3.8ghz handle ddr3 2133mhz

if your motherboard allows you to run 2133 ram whether it be with the OC stipulation (2133/OC) or just out the box you can use it. but you will be limited to 1 stick per channel so 3 sticks total as its a triple channel chipset.
to be able to use more than 1 stick per channel you have to use ram that the cpu's mem management unit handles natively, ie 1333 will allow you to use all six ramslots if your boards has them...

the real world advantages of running 2133 ram are insignificant on that cpu even when your doing things like raring files which is about the only thing that gets real world benefit from faster ram... in benches you will get higher numbers for bandwidth but that doesnt translate into real world performance gains on that cpu/chipset/architecture for things like gaming, movies, web surfing and most productivity.
 

Tradesman1

Legenda in Aeternum
It will depend on your CPU's MC and how many sticks you are thinking of running, can't think of any tri channel sets offhand that run 2133, so guessing you are thinking dual channel, would help to know how many sticks, the model of the sticks and what mobo, think best bet if wanting tri-channel would be 1866
 
ive used 3 sets of dual channel 1333 ram in a socket 1136 and it worked perfectly fine in triple channel mode. ive also used 2 sets of dual channel 1600 ram and had to dump 1 of the sticks because of the 1 stick per channel rule and again it worked perfectly fine in triple channel mode. as long as the ram can be used in more than 2 stick combos there should be no issues with dual channel rated ram running in triple channel systems.
 

Tradesman1

Legenda in Aeternum
That's why it's best to use DRAM from full sets, not mix sets, generally with low end DRAM like 1066, 1333 iit will often play together , you have low freq and loose timings, I've had6 sticks of 1866 before in the 1366 socket and they were fine, of course needed a good OC on the CPU to help the MC carry the sticks and additional voltage, running 6 sticks at 1333 or 1600 shouldn't be an issue, though only time I've seen problems was with CPUs that had a weak MC
 
odd that. every time i tried to use more than 3 sticks running faster than 1333 half the ram disappeared in windows. it was fine in bios but as soon as i got into windows it would often be gone(was unstable). i emailed intel about this and they told me specifically that the intel i5/i7 mmu (mc) limited the system to 1 stick per channel when you go over 1333 for the original neph platform and still have the same limitation up to 1600 and 1866 on the newer sandy and ivy parts respectively and depending on the cpu used (depending on the mmu max native speeds).
 

Tradesman1

Legenda in Aeternum
Not odd, that's Intel and it's crap...sounds like it came back in the early-mid 1366 days...and prob from someone who thinks thought they were smart, for them to say something about 'newer sandy and Ivy) is completely ridiculous....as it is with the 1366, if it even had a hint of truth (especially from that timeframe (when 4GB sticks were Boss) then NOBODY would be running 16 or 32GB in SB or Ivy, which obviously isn't happening, I've had 32GB in my SB from the release (originally 1866 then kicked up to 2133), IB I started wed with 32GB of 2133 and licked it to 2400, and have built about 26 rigs since SB was released that started with 32GB of 1866 or better...and have seen well over a hundred wigs running 1866 or better w/ four sticks of 4GB