MSI X470 Gaming Pro. The articles I've seen often mention 16GB sticks but a few have mentioned 32GB sticks with the later 3600 cpu.Which motherboard? What is the main purpose for your system and how much memory do you have currently? And at what speed are they running at with xmp/docp enabled?
Usually two dimms is easier on the cpu memory controller. Not that four sticks won't work, just it's less hassle getting two to work if you run into issues. Depending on your motherboard, if it says max 64gb, divide that by how many dimm slots there are and that'll be max memory size per slot.