AMD on their website started direct sales of processors and graphics cards, much like what NVIDIA is doing with he founder edition graphics cards. So if you yearn that Ryzen 9 3900X and there is no availability in etail, hey check the AMD on stock and you can purchase it there.
Obviously, as far as the graphics cards go, the products are reference models and all are available in North America, Western Europe, Asia-Pacific, greater China and Latin America. The custom cards from AMD’s partners such as MSI, ASUS and Sapphire (which are due to appear in mid-August and September) remain exclusively for sale through manufacturers. Currently, AMD offers the AMD Ryzen 3900X Processor and AMD Radeon RX 5700 Series Graphics Cards on their website.
Links to the sales pages: