Fanless Mini PC with Intel Celeron J4125 Quad-Core Processor | 4x Intel I225 Gigabit LAN Ports | 8GB RAM & 64GB mSATA SSD | VGA/HDMI/USB Connectivity | AES-NI Encryption - Ideal for Home Firewall, Network Security & Small Office Server Applications

The case is fairly thick and the finish feels good in your hand. Flipping it over you'll see 4 screws in the corners to remove the bottom plate. There are extra holes for mounting a 2.5" drive which are offset to one side to accommodate the drive connectors. I'm not sure what the other set of holes are for. Speaking of holes... they give you a pack of screws that is generous enough to build out 3-4 of these. I purchased the stripped down version and threw in a spare SSD drive and RAM. They also provide a short SATA cable and power plug that routes nicely inside the case between the motherboard and drive. In case there is any question, there is only one RAM slot. The documentation claims to support a max of 8GB which is what I installed... I don't have a 16GB stick handy to verify if it could actually handle more. You can see from the pictures that there are some extra unexpected goodies. For instance, there is an extra power connector available by the native power port. If you pull the NIC side plate off from the case (only 2 screws on the sides), you could easily land extra power and fish it out one of the side vents to give it redundant power feeds. There are extra landing pads for a COM1 connection. There's an extra unused USB 2.0 pin header near the SATA power port. There are also some mystery jumpers/pins I wasn't able to identify. In the corner by the SATA connector is a pin header that looks to perhaps be for power button and lights... which would be redundant to what's already provided... so, I'm not sure exactly what one would use those for. Remote control status and reset monitored by a Raspberry Pi maybe??? Also, near each of the NIC ports are a set of mystery jumpers... JI226, JI227, JI228... I have no idea what those are for.Others that were expected were the MSATA, SIM and Mini PCIe slot. About the only thing worth mentioning on these is that depending on your PCIe card, it may bump up against the SATA connector if you are using a 2.5" drive. I don't have a card on hand to test the clearances. I also wasn't able to test if the MSATA and SATA port were linked and therefore exclusive of one another, of if you could run both at the same time.Other than that, you can see that this unit uses the Intel I225-V Ethernet Controllers which are rated for 2.5Gbps. These are the Intel chips in the pictures with "SLNMH" stamped on them. When I loaded up pfSense 2.6.0, everything was recognized straight away and worked flawlessly. In the picture the MAC addresses are all sequential which for some systems will determine the order of ETH0, ETH1, etc.. pfSense picked them up in the exact order that they were labeled on the case.Out of curiosity, I also tried to load up Sophos XG Firewall Home Edition version 18.5.2.380 and that didn't go so well. For starters, Sophos would only install using Legacy BIOS rather than UEFI which took a few setting adjustments to force that. And then once installed, it wouldn't recognize any of the NICs... they apparently don't have drivers installed for the I225-V chips. A shame really because I do like Sophos. There are two other versions of this firewall that use the I210 and I211 chips... perhaps being older chipsets there will be better success with Sophos on those models. To be fair though, I also didn't reach out to Sophos to see if there's any workaround for the UEFI boot or the NIC drivers.Speaking of installing Sophos though... That does remind me of one other feature I wasn't entirely expecting... an internal speaker! I only mention it because there are some standard beeps and chirps at startup that initially I ignored... but the Sophos installer actually plays music through the speaker when the install is complete to prompt you for a reboot. It made me chuckle because I've never heard the music play before and it reminded me of something straight out of a 90's video game.I haven't done any extended line rate tests with crypto or anything to stress the unit. But, it barely draws any power at idle and the case is just barely above room temperature. I connected a USB PowerDelivery 12V trigger module and a USB power meter to the aforementioned aux internal power connector (for reference, the pin closest to the stock barrel jack is positive). I was running pfSense from a 2.5" Kingston 120GB SSD, and had one WAN and one LAN port connected. At boot the unit momentarily drew 8 Watts. Once boot was complete, it idled down to just under 6 Watts. With the unit off, but the two network connections still showing active link lights (WOL support) the unit drew just under 2 Watts. All in all... a very power efficient package.Anyway... all that said, I did actually purchase two of these and have them running as an HA pair with pfSense. Everything seems to be running smoothly so far. I would definitely recommend this as a DIY pfSense firewall over purchasing a lower end Netgate appliance. Even as you approach the $1000 appliances, the only thing they really have more than this unit are more/different ports. But, the Intel J4125 in this unit should (stress "should") outperform the C3558 processor in the lower appliances for any CPU bound operations. Not to mention... this unit has 2.5Gbps ports... which you don't see until you get to the Netgate 6100 which costs over double what this unit costs. Anyway... two thumbs up. I'm a happy owner.