There are a couple 16 GB DDR4 SODIMM memory modules out there, but not very many. However, Kingston is filling the gap with new HyperX modules, which it uses in six new memory kits in its DDR4 Impact line.
The 16 GB DDR4 SODIMM modules will exist in two variants, one with a 2133 MHz frequency and the other at 2400 MHz. The latencies depend on the kit they're in, although the lower-frequency model has slightly quicker timings, as is usually the case.
Of the six kits, three will be 2133 MHz and three will be 2400 MHz. Capacities will include 16 GB (consisting of a single module), 32 GB with two modules, and 64 GB with four modules. The 16 GB and 32 GB 2133 MHz kits will have CL13 timings, whereas the 64 GB 2133 MHz kit will have CL14 timings. The 2400 MHz kits are each one tick slower, meaning that the 16 GB and 32 GB kits run at CL14, with the largest and fastest 64 GB 2400 MHz kit running at CL15.
All the kits run at 1.2 V, operate between 0°C and 85°C, and work with the Intel 100-series chipsets. Naturally, they carry XMP support, so setting them up to run at the correct frequency shouldn’t be much more difficult than snapping your fingers.
Prices range from $109.00 through $445.00, you can order them directly from Kingston immediately. Over the coming weeks we should see them show up at re- and e-tailers.
Update, 3/10/16, 8:15pm PT: Fixed typo.