You don't have to upgrade your motherboard for the new Ryzen processors

[Windows Central]

Best answer: No. While there will be new motherboards available with the X570 chipset to go with the third generation of Ryzen processors, if you're upgrading from a previous generation you can just reuse your motherboard as long as you update the BIOS.
Top AMD motherboard: MSI Gaming Plus X470 ($130 at Amazon)

Full story from the WindowsCentral blog...