I7 5820K only support DDR4 2133 Max?



Yes, you can then enable XMP in the BIOS. You might have to OC your cpu a little.

I have a 5930k and have my ram running at 3000mhz with a slight cpu overclock.
 


When i installed the RAM it was underclocked to 2133mhz until I enabled XMP. You can also do it manually.
Cl is CAS Latency. If you can, get the lower number but performance difference will be negligible.
 


Yup. You will have to overclock your cpu a little to get it to 3400mhz though. Like I said out of the box it will be running at 2133mhz, 3400mhz is what it is tested up to so you can enable xmp to get it there.