Yeah, old Xeons tend to not be very low power, also I don’t think I’ll be able to find one with a mini ITX board to fit it in a compact case. Also, I’d probably need to add a discrete GPU, which adds to the cost and power consumption.

I want a low power build to limit heat and noise produced in my office room, to limit the electricity bill and as I understood it the case I’m considering also doesn’t have the best thermals, so I don’t want to put a CPU with too high a TDP into it.

The ReadyNAS 626 actually has a Xeon D-1521, but with a quite low TDP - 45W.

Regarding budget, I’m aiming for 400-800$. The N100 option, including case and PSU (but not disks) is at the lower end of this, while the 8500G and 13100 options are at the upper end.