If you're going to buy a Z170 board, it's completely fine. The only thing you'll need to do after building and getting your OS fully set up, you'll wanna head over to the manufacturer's website, search and find your motherboard, and there will most likely be a "BIOS Flash" section in the "Downloads" section for your motherboard. You'll want to load that onto a removable USB stick, restart your computer, mash whatever key takes you to your BIOS, and look for the option that says "BIOS Flash", then click your way through the settings, it will restart 1 to many times, and you'll have your motherboard ready for 7th Gen. (You do this all after installing, so you don't need to worry about having that 7th gen CPU in for that short amount of time, but you want to do it very soon after you're fully set up.)