Lets look at Samsungs specs for DDR4 (and this is not LPDDR4, just standard DDR4). http://www.samsung.com/global/business/semiconductor/file/media/DDR4_Brochure-0.pdf Quote: "DDR4 consumes 37 percent less power than DDR3L when running an identical process at the same speed. DDR4 adopts a Pseudo Open Drain (POD) interface to reduce I/O power consumption and increase power savings by 50 percent compared to DDR3L under 4 Gb-based 16 GB 2 DIMMs per channel (DPC) conditions." So if I'm reading this right, 16GB DDR3L uses double the power as 16GB DDR4 under load (blue+red part). And when idle 16GB DDR4 uses 28%'ish less power (blue part). "Power concerns" my ass. Edit: updated numbers.