Good CPU for Jellyfin and ZFS

[FunctionDJ]

For the record the current version of Jellyfin, 10.8.11, does not yet support transcoding TO AV1.  But definitely great if your devices support AV1 for high quality, lower bit rate, direct play.

1)  If you are not married to the requirement to use ECC memory and
2)  Don't have much or any 4K HDR content

An 11th gen+ Intel desktop CPU would serve your needs.  I recommend 12th gen+ because they finally got off of the 14nm process.  The iGPUs in 11th gen+ are very capable for non-HDR transcoding.  You only have AV1 DECODE support, though.  If you have a lot of HDR content you should probably get an Intel Arc GPU since HDR tone mapping to SDR requires a lot of compute that iGPUs just don't have for more than 1 or two streams.

If you do require ECC, make sure the MOTHERBOARD supports ECC.  All Ryzen CPUs support ECC, but the board maker has to allow that to be turned on in the BIOS.  And you definitely need a dedicated GPU (again, recommending Intel Arc) because none of the AMD iGPUs perform well with transcoding.

Regardless, max out the supported memory.  ZFS will make use of every byte you have.

I'd really like to use ECC memory to have a little less risk of writing bad data to disk, and i do have a lot of 4K HDR content. And while i'm going to consume it through HDR capable devices like my TV and phone, the other users might not, so good tonemapping support would be great.
I know that the motherboard needs to support ECC too but i wanted to start with a CPU and go from there, but still thanks for letting me know

So it seems like the "ultimate solution" would be a Ryzen CPU that only needs to be as fast as i need all my other compute to be (i'm probably gonna go second-hand 5600 or similar) paired with the Intel ARC 310, right?

Finally, regarding memory with ZFS, it's true that ZFS can take advantage of more RAM but it can also run fine with just a few GB. I'll most likely spec the server with 2 x 16GB sticks with good clock rates to allow me to add 2x16 later on if i need to.