The verdict

CPU
Minisforum N5 Pro has 8.3x the CPU throughput (33,292 vs 4,000 PassMark).
Plex
Minisforum N5 Pro transcodes more 4K HDR streams (~5 vs ~4).
Idle power
QNAP TS-664 idles lower (16W vs 33W) - cheaper to run 24/7.
RAM ceiling
Minisforum N5 Pro takes more RAM (96GB vs 16GB).

Which wins for each job

Job Minisforum N5 Pro QNAP TS-664
Plex / Jellyfin ~5 streams win ~4 streams
Frigate NVR add a detector ~4 cameras win
Proxmox / VMs 33,292 PassMark win 4,000 PassMark
Firewall / router 2 NICs 2 NICs
Local AI / LLM PCIe GPU slot PCIe GPU 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 QNAP TS-664
Price (list) $899 $799
CPU AMD Ryzen AI 9 HX PRO 370 Intel Celeron N5095
Cores / threads 12 4
PassMark 33,292 4,000
iGPU Radeon 890M (RDNA3.5) Intel UHD (16 EU)
NICs 2 2
NIC model Marvell AQC113 10GbE plus Realtek 5GbE Intel I225-V
RAM max (GB) 96 16
M.2 free 3 2
PCIe slot x16 x4
Idle (W) 33 16
TDP (W) 54 15