So a few ideas:
You'll get many more reads and responses if you post this in the Systems forum. Also, I would suggest that you include a budget. State if that budget includes the monitor cost, or if you already own them. Do you live in the US, or another country? If another country, then state a website that you feel comfortable buying PC components from. I would also have a goal stated. For example, "I want to game on a Fallout 4 with a triple 1080p setup at 60 FPS."
Yes, a skylake CPU and Z170 motherboards support DDR4. How much RAM? 8 GB minimum but 16 is particularly nice to have in general, although not required to get the most out of games.