What is the TDP?

Why does it matter? I mean, what are you trying to do? Most users don't care about the TDP of ram sticks.

TDP stands for Thermal Design Power, and allows OEMs to plan for the amount of heat parts will generate while being used. For example, a 35W CPU will emit less heat than a 95W CPU. OEMs need this info so they know which HSF to use, how large a PSU, etc.

Edit: Forgot to mention. I know 5W has been listed before in the past, but that was back when we used DDR2. Which has a much higher voltage then DDR4. I've seen 2.5W listed for some DDR3 sticks, I would assume a two stick DDR4 combo uses 5W, not 5W each for 10W total.