The verdict

CPU
Beelink SER7 has 2.6x the CPU throughput (28,351 vs 10,800 PassMark).
Idle power
iKOOLCORE R2 idles lower (9W vs 14W) - cheaper to run 24/7.
Networking
iKOOLCORE R2 has more NICs (4 vs 1) - better for a firewall or VLAN trunk.
RAM ceiling
Beelink SER7 takes more RAM (64GB vs 16GB).

Which wins for each job

Job Beelink SER7 iKOOLCORE R2
Plex / Jellyfin ~5 streams ~5 streams
Frigate NVR add a detector ~4 cameras win
Proxmox / VMs 28,351 PassMark win 10,800 PassMark
Firewall / router 1 NICs 4 NICs win
Local AI / LLM no slot 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 Beelink SER7 iKOOLCORE R2
Price (list) $399 $389
CPU AMD Ryzen 7 7840HS Intel Core i3-N305
Cores / threads 8 8
PassMark 28,351 10,800
iGPU Radeon 780M (RDNA3) Intel UHD (32 EU)
NICs 1 4
NIC model Realtek RTL8125 Intel I226-V + Realtek 2.5GbE
RAM max (GB) 64 16
M.2 free 1 1
PCIe slot none none
Idle (W) 14 9
TDP (W) 54 15