When purchasing a motherboard, arguably the most important factor is compatibility with your CPU. Each motherboard has a socket that can only fit some types of CPUs, so you want to be careful about what you're purchasing. You also must choose a good, compatible CPU, and it is also useful to know how to tell which generation the CPU is.
AMD has done its best to ensure future compatibility with its sockets. For home and small business systems, they use a series of sockets called "AM", and for server-grade CPUs they use a socket called "TR".
Processors
Currently, AMD has three processor lines: Ryzen, Athlon, and Threadripper. Ryzen and Athlon are meant for single systems, although Ryzen is quite a bit more powerful than Athlon. Ryzen starts at 4 cores with their Ryzen 3 processors, and goes up to 16 cores (currently) with the Ryzen 9 3950X. Athlon operates in the 4-6 core area and are meant to run simple tasks.
One important thing to know is that Ryzen 9 is NOT necessarily a higher series than Ryzen 3; in fact, it's possible that a Ryzen 3 processor is a higher series than Ryzen 9. The numbers after "Ryzen" are just a general guideline of how powerful it is. The series is the thousands place of the numbers AFTER Ryzen [number]. For example, the Ryzen 3200g is of the 3000 series of Ryzen processors. A Ryzen 5 2600 is of the 2000 series. Series are released all at once; for example, the Ryzen 7 3800X, the Ryzen 3 3200G, and the Ryzen 5 3600 were released around the same time.
For Athlon processors, the classification is a little more opaque, although they do sometimes follow the classification of the Ryzen processors. For example, the Athlon 3200G is in the same generation as the Ryzen 3 3200G.
Lastly, we have the Threadripper series, which are AMD's High-End-Dekstop (HEDT) processors. These are where AMD's smaller transistors shine, which allows them to fit a vomit-inducing 64 cores and 128 threads. These are processors meant for people doing advanced 3D modeling, entire-office systems, AI learning, etc. Even for the most advanced games, this processor is lightyears beyond overkill. Threadripper processors are classified in the same way as Ryzen processors, and are in the same generations.
Sockets
AM
The AM socket is meant for AMD's small-system processors. Currently, we are on the AM4 socket, which is the fourth iteration. AM4 sockets hold Ryzen and Athlon processors, of any generation. The AM4 socket is why many people choose AMD over Intel. If you had bought an AM4 socket motherboard when it came out, you would have compatibility for over five years, upgrading or downgrading to any processor you'd like. This not only allows you to keep your motherboard but also your digital Windows license, which saves you massive amounts of money.
TR
The TR socket is a fairly new socket designed for AMD's server-grade processors, which are currently just the Threadripper series. The current generation of the TR socket is TR40X, although unlike the AM socket, it is not on its 40th iteration. It is quite a bit bigger and is usually on massive motherboards with 8+ DIMM slots.
Overall
The three main things you should look for with AMD sockets are compatibility with your processor. Mostly, it's just AM4 socket can connect with Ryzen processors, which is a godsend to new PC builders. You should also check which generation or processors your motherboard is compatible with. We hope our guide was helpful. Have a great day!