Motherboard: M5A97 R2.0
CPU: AMD FX-8320E Eioght-Core Processor
Upgrade to or upgrade from?
Those two will work together but if want something else, as said will require new mobo and DDR4 memory.
Are you a gamer? If so what GPU do you have?
Guessing game oriented, If like to continue with Amd, it's Ryzen CPUs are doing really well, will surely notice a difference.
To get you started;
https://www.google.com.au/amp/s/pcmasterracebuilds.com/blog/the-best-ryzen-gaming-pc-builds-1080p/%3famp
Google Ryzen benchmarks to get a grip on performance numbers in games between cpu models. Once happy on a particular processor, google best motherboard for that processor. Theres plenty good suggestions on here at Tom's, Anantech, Reddit and linustechtips that'll surely show up in your search results.
DDR4 with its low voltage of 1.2v and 1.35v is another change, Intel as well. They no longer use DDR3. 1.2v memory for stock memory speeds without overclock. If faster memory is supported, the motherboard memory specifications will describe them with an (OC) next to the memory frequency at the motherboard specifications page. you'll find those memory modules operate at 1.35v for the extra speed.
If going Ryzen, these CPUs crave memory speed so if/when looking for ram go for the highest the motherboard will allow and always go 2x sticks for dual channel as it doubles the memory bandwidth and aim for 16GB ram minimum. 8GB isn't enough in games today with video cards more than 4GB vram.