Firewall Mini PC N355 Upgraded N305 - 6x 2.5GbE Fanless Firewall

In this review the Firewall Mini PC N355 is evaluated as a compact hardware appliance aimed at small offices, home labs, and network hobbyists who need multi-gigabit routing with low power and silent operation. The single biggest reason to consider it is the combination of six 2.5GbE i226V ports and a low-power 12th Gen N355 CPU, which together offer real-world throughput and AES-NI acceleration in a fanless micro chassis suitable for OPNsense and other firewall operating systems.

Key Features

• 6 x 2.5GbE LAN: Six Intel i226V ports provide 2.5x the bandwidth of gigabit for more responsive LAN routing and multiple WAN or LAN segments without immediate need for additional switches.
• 12th Gen N355 Processor: The Twin Lake N355 with 8 cores and AES-NI delivers enough CPU headroom for VPN, IDS/IPS and deep packet inspection tasks while keeping power use low.
• DDR5 and NVMe Expandability: Single DDR5 SO-DIMM support and two M.2 NVMe slots plus a SATA 3.0 bay allow fast system storage and room to grow for caching or logging.
• Fanless Micro Design: The passive chassis runs quietly for desktop or closet placement, with an optional small 12V 4-pin fan supported if active cooling is later required.
• Triple Display and I/O: Dual HDMI and a Type-C video output support 4K@60Hz for local console use, plus USB3.2, multiple USB2.0 ports and a TF card slot for flexible management and storage.

Who It's For

This unit is best for small business IT administrators, lab enthusiasts, and prosumers who want a dedicated hardware firewall appliance with multi-gigabit LAN ports and the ability to run OPNsense, OpenWrt, ESXi or Linux images. Its combination of AES-NI capable CPU and multiple 2.5GbE ports makes it practical for VPN termination, site-to-site tunnels, and modest IDS/IPS loads.

Those who need enterprise-class throughput well above multi-gigabit, redundant power, or rackmount form factors should look elsewhere. Also, buyers expecting a fully assembled server with lots of internal memory preinstalled should note this model uses a single DDR5 SO-DIMM slot and may require separate RAM or storage upgrades for heavy use.

Pros & Cons

Pros

• Six Intel i226V 2.5GbE ports provide flexible WAN/LAN segmentation without extra NICs.
• Low-power 12th Gen N355 processor with AES-NI handles VPN and security services efficiently.
• Fanless design ensures silent operation suitable for office or home placement.
• Good expandability with 2x M.2 NVMe slots and a SATA 3.0 bay for storage needs.

Cons

• Only one DDR5 SO-DIMM slot limits out-of-the-box memory capacity compared with larger appliances.
• Not rackmount or redundant by default, so larger enterprises will need different hardware.

Specifications

Processor	12th Gen N355 Twin Lake, 8 cores/8 threads, up to 3.9 GHz
Network	6 x Intel i226V 2.5GbE LAN ports
Memory	1 x DDR5 SO-DIMM slot, 4800 MHz
Storage	2 x M.2 2280 NVMe PCIe 3.0 slots; 1 x SATA 3.0 for 2.5" SSD/HDD (cable included)
Graphics & Display	Integrated UHD Graphics (32 EUs) with 2 x HDMI + Type-C supporting 4K@60Hz
Design	Fanless micro appliance; optional 12V 4-pin fan supported (cable included)
OS Compatibility	Windows 11 Pro pre-installed; supports OPNsense, Linux, ESXi, OpenWrt

Our Verdict

The Firewall Mini PC N355 is a well-rounded micro firewall for small networks that need multi-gigabit LAN and efficient VPN or inspection workloads. It is good value for users who want a quiet, expandable appliance that runs OPNsense or similar software and offers six 2.5GbE ports natively; larger sites needing rackmount redundancy should consider a different class of device.

Frequently Asked Questions

Can this run OPNsense out of the box?
Yes, the unit supports OPNsense and other firewall distributions, though OS installation may require configuring BIOS boot settings via the Delete key.

How many drives can be installed?
Two M.2 NVMe drives and one 2.5" SATA drive are supported, with a SATA 3.0 cable included for the 2.5" bay.

Is it truly fanless?
The chassis is designed for fanless operation, but a small 12V 4-pin fan is supported and a fan cable is included if additional cooling is desired.