Transcoding anything >720p is painful.
I run ancient hardware for desktop/laptop >10yrs old apple stuff running linux. I consume media mainly via rpi4 or android.
What’s a minimum level system capable of trans-coding 4k video to x265 in at the very least real time? Is there a tiny trans-coding device out there somewhere?
Would a NUC do? How old or new to churn out 4k x265
Can I avoid hardware? Are cloud gpu’s a thing?
If you want real time transcoding, then a hardware encoder would be best. Intel CPUs have had hardware H.265 encode support for the last 8 years. Intel ARC GPUs have a very good video encoder, but they require system that supports resizable BAR.
If you just want to transcode a large number of videos for storage, get a system with loads of CPU cores and run multiple transcodes in parallel. Software encoders produce higher quality video than hardware encoders.
There are cloud GPUs, but that gets very expensive, very fast. You are much better off buying your own hardware if you need to use it for a longer period of time.
The encoder engine is the same for all ARC GPUs, meaning you can by the lowest end one and it has the same encoding/decoding performance as the top tier one.