Kingston recently smashed the DDR4 frequency record at 4351Mhz by overclocker Toppc from MSI using one 4GB HyperX Predator 3333MHz DDR4 module on the new MSI X99S XPOWER AC motherboard,
We are not sure of what cooling was used but we can pretty much guess LN2 was involved.
A validation link can be found here : http://valid.canardpc.com/08a7ls
Along with a video in YouTube https://www.youtube.com/watch?v=FLcVFGVs2Xk
As of now Kingston hold top 3 memory records in HWBOT http://hwbot.org/benchmark/memory_clock/halloffame