The verdict

CPU
Minisforum N5 Pro has 1.1x the CPU throughput (33,292 vs 29,825 PassMark).
Idle power
Minisforum UM790 Pro idles lower (11W vs 33W) - cheaper to run 24/7.
Networking
Minisforum N5 Pro has more NICs (2 vs 1) - better for a firewall or VLAN trunk.
RAM ceiling
Minisforum N5 Pro takes more RAM (96GB vs 64GB).
Local AI
Minisforum N5 Pro has a PCIe slot for a low-profile GPU - the other needs a DIY build for local LLMs.

Which wins for each job

Job Minisforum N5 Pro Minisforum UM790 Pro
Plex / Jellyfin ~5 streams ~5 streams
Frigate NVR add a detector add a detector
Proxmox / VMs 33,292 PassMark win 29,825 PassMark
Firewall / router 2 NICs win 1 NICs
Local AI / LLM PCIe GPU slot win no slot

Approximate - capacity estimates from curated specs, the same logic as the recommender. Verify against your exact setup. Prices move; check the retailer.

Full specs

Spec Minisforum N5 Pro Minisforum UM790 Pro
Price (list) $899 $439
CPU AMD Ryzen AI 9 HX PRO 370 AMD Ryzen 9 7940HS
Cores / threads 12 8
PassMark 33,292 29,825
iGPU Radeon 890M (RDNA3.5) Radeon 780M (RDNA3)
NICs 2 1
NIC model Marvell AQC113 10GbE plus Realtek 5GbE Realtek RTL8125
RAM max (GB) 96 64
M.2 free 3 1
PCIe slot x16 none
Idle (W) 33 11
TDP (W) 54 54