So G.Skill complete offerings start from DDR4-2133 with up to 16GB capacity per module and end at 4GB modules with speed DDR4-4000.

So we are at speeds, where is likely no DDR3 maker dare to go. The price is, of course, higher voltages and crappier timings. Insread of somewhat "standard" 1.2V for DDR4 kits expect a 1.35V and timings at CL 19 - 25 - 25 - 45 values. Not exactly my dream timings… whatever happend to the 1.5 - 2 - 2 - 5 DDR1 G.Skill modules?!

Of course, there are lower clocked modules too:

So for the Haswell-E and for upcomming Skylake-S with chipset Z170 G.Skill have the need rams. The 4 000MHz sticks use the fastest Samsung chips and are validated to run on ASRock Z170 OC Formula mainboard. Next boards should follow… Using the DDR4-4000 is possible by using XMP 2.0 profile, of course the are standard JEDEC basic profile(s) too.

So it looks lik G.Skill have to bin thru Samsung ram chips to create these highest clocked rams. So right now, we have there chips makers for DDR4 - Micron is slow, Samsung is quite good and Hynix is allegedly the best, according to some overclockers.

I would like to see tighter timings  😛