I built my original unraid rig back in 2017ish. I have planned for about 2 years to update the hardware but various life events have prevented me from doing it. The reason for upgrade would be to add more users to plex, right now I feel like I am maxed out at about 5 concurrent streams with all the other stuff running. Last October my best bud of 30 years died suddenly of a rare, aggressive cancer. His wife asked me to take his computer that he built a few years ago and use whatever I could for unraid, I just picked it up last week. I got out of tech in 2020 and after that I have kind of ignored my system, only changing hard drives when I was out of space and doing nothing else. With all the crazy prices right now I am at a loss of what I should do. I have about $750.00 saved but I would also like to use what I can from his setup. I am attaching a photo of my current specs and his specs. He also has a Radeon RX 6650 XT Mech 2X 8G that is not listed. I would also like to add a second parity but that would mean a new case so that will probably have to wait. Any feedback would be appreciated. Thank you.

His Ryzen is a giant improvement over your CPU. Just combine both sets of memory + the Ryzen.

Plex is a separate issue. Why do you feel that 5 concurrent streams is the max you can currently support? Are the streams regularly transcoding? If so, you'll need to pick up a GPU - look for an Intel Arc, a great, unlimited GPU for transcoding. You need to know what your actual issue is with plex to get a better idea of what you need to do.

On the Plex issue.

I was also running a Windows VM that was used for Blue Iris and an ebook private tracker because I couldn't figure out how to incorporate it into a docker with the sharing rules. When that was running the CPU was pretty much maxed out the entire time. I have since deleted it.

Additionally, when I took the trip to pick up the computer I witnessed the plex use of 3 of my users I I was not happy with the performance they were getting. They are all very close with me and they never complain but they were turning everything way down to 480 just to get a smooth stream. In looking at their use right now it is mostly transcode and the most common devices are roku and apple tv. I know I probably need to look more closely at my plex setup but I wanted to start with hardware if I could.

Blue Iris is a hog, so yeah, that would do it (if you're still running it).

Move your Unraid to the new CPU + combined RAM and test everything. See how it goes. Worst case, you move Blue Iris to your old machine by itself, or even move Plex to your old machine by itself.

You could also upgrade your old CPU, assuming your old MB supports maybe an 8th gen or 9th gen (I don't actually know if it does). If so just bumping it up to an 8th Gen with iGPU would give you a boost as well. You've got choices with what you have on hand, so be patient and test things out. That way you can make the most efficient choices for what you decide to buy. Maybe just an old CPU? Maybe you just need 16GB of DDR for your old machine (because you increased your new Unraid box to 32GB).

Since your users are transcoding, you either need to get your content into a compatible format(s) or pick up a GPU like an Intel Arc. It doesn't have the same limits that Nvidia GPUs have and handles everything thrown at it (so far). The AMD based GPU isn't a great choice for transcoding video. <--- this assumes you are currently using your existing iGPU and it is not keeping up with the workload. If you have not enable Plex to use your iGPU, you need to try that before you do anything else.

Edited 16 minutes ago16 min by whipdancer