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

In this review of the Firewall Mini PC N355 the bottom line is straightforward: this micro appliance is aimed at small offices, home networks and prosumers who need multiple high-speed LAN ports and solid processing in a compact, fanless chassis. The reviewer found the combination of a Twin Lake N355 CPU, 6 x 2.5GbE i226V ports and DDR5 expandability makes it a practical hardware platform for OPNsense, OpenWrt or Windows 11 Pro environments where throughput and low-noise operation matter most.

Key Features

• 12th Gen N355 Processor: An 8-core, 8-thread Twin Lake N355 CPU delivers responsive packet handling and modest application performance while keeping power use low.
• Six 2.5GbE LAN ports: Six Intel i226V 2.5GbE ports provide multi-segment connectivity and higher throughput than gigabit without needing additional NICs.
• DDR5 and NVMe storage: One DDR5 SO-DIMM slot and two M.2 NVMe slots plus a SATA 3.0 bay let users add fast RAM and multiple storage devices for OS and logs.
• Fanless micro appliance: The passive design ensures quiet operation suitable for office or lab racks, with an optional small fan supported via included 4-pin cable.
• Flexible OS support: Ships with Windows 11 Pro preinstalled but explicitly supports OPNsense, Linux, ESXi and OpenWrt for firewall and virtualization use cases.
• Triple display and Type-C: UHD integrated graphics with 2x HDMI and a Type-C port allow 4K@60Hz output for local management or monitoring consoles.

Who It's For

This appliance is best for network professionals, small business owners or advanced home users who need multiple high-speed LAN interfaces and a low-noise, compact firewall platform. It suits deployments that require 2.5GbE connectivity between subnets, uplinks or to storage devices without adding external NICs.

Those seeking a simple consumer desktop, heavy GPU compute, or a turnkey consumer router with cloud-managed ease should look elsewhere; this unit is designed for on-premise firewall, routing or virtualization tasks and expects the user to provision the OS and configuration.

Pros & Cons

Pros

• Multiple Intel i226V 2.5GbE ports mean flexible network segmentation and higher throughput than gigabit switches.
• DDR5 support and dual M.2 NVMe slots offer modern memory and storage options for OS performance and logging.
• Fanless chassis keeps noise to a minimum while optional small fan support helps thermal headroom in dense racks.
• Wide OS compatibility makes it suitable for OPNsense, Linux, ESXi and Windows 11 Pro installations.

Cons

• Single SO-DIMM slot limits maximum memory upgrade flexibility compared with larger appliances.
• No built-in hot-swap drive bay; internal SATA requires opening the chassis for 2.5in drives.

Specifications

Processor	12th Gen Twin Lake N355, 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 PCIe3.0 slots + 1 x SATA 3.0 for 2.5in drive
Graphics/Display	Integrated UHD Graphics, 2 x HDMI + 1 x Type-C, up to 4K@60Hz
Cooling	Fanless design; supports optional 12V 4-pin 80x10mm fan (cable included)
Included	Firewall appliance, power adapter, SATA 3.0 cable, 4-pin fan cable

Our Verdict

The Firewall Mini PC N355 is a practical choice for anyone needing on-site firewall or router hardware with multiple 2.5GbE ports and modern memory and storage options. It balances low power, silent operation and flexible OS support to deliver strong value for small offices and tech-savvy home networks, though users wanting easy drive swaps or larger memory capacity may prefer a different chassis.

Frequently Asked Questions

Can this run OPNsense or other firewall OS?
Yes. The unit supports OPNsense, Linux, ESXi and OpenWrt in addition to the preinstalled Windows 11 Pro.

How many high-speed network ports does it have?
It provides six Intel i226V 2.5GbE ports, suitable for multiple uplinks and segments.

Is the unit noisy?
The design is fanless for quiet operation; a small 12V 4-pin fan can be added using the included cable if extra cooling is needed.