Recently, I was running out of processing power on my Raspberry Pi 3. I was running Asterisk PBX, OpenVPN Server, and several sensor monitoring and MQTT applications. I wanted to add MySQL Server, but figured that might be pushing things.
My first thought was to run an old desktop PC. However, I was a bit short on physical space, and didn’t really want a large desktop box. So I started researching mini-PCs. I wanted something as powerful as a low-end PC. Something that didn’t take up much space, and with as few mechanical parts as possible. After researching what was available, I decided to go with a model made by Qotom. The model I purchased has an Intel quad-core processor, and 8GB of RAM. Just like a desktop. A big plus is that is has 4 Ethernet ports. That could be useful if I decide to make my own router some day.
This mini-PC consumes a maximum of 10W of power. This is significantly less than a classic desktop. I had an old quad-core desktop with comparable specs. I measured its power consumption – it varied from just over 40W when idle, to over 80W when running CPU-intensive tasks. The Qotom has no moving parts. There is a large heat sink in place of a fan, and the hard drive is solid state. I wondered, though, if a heat sink and no fan would actually keep the device cool. Turns out, it does. Here is a thermal picture:
As you can see, the temperature of the mini-PC (while running Asterisk, OpenVPN, MySQL Server, and several other applications) is around 86 degrees. This is about 15 degrees warmer than the ambient room temperature, and is comparable to the temperatures of other electronics such as the router and phone.
I created installation media for Ubuntu Light Linux (Lubuntu) using a standard USB thumb drive. The operating system installation process was almost identical to that of an ordinary PC. I connected a monitor and Ethernet cable, plugged in the USB keyboard, mouse, and thumb drive, and proceeded with installation. Because of the SSD hard drive, it actually went faster than on an ordinary desktop PC. In under an hour, the software, as well as all live updates, was installed. Initially, the machine booted up to the desktop GUI. Once I installed OpenSSH to allow me to access the computer through secure shell, I disabled the GUI, and disconnected the keyboard, mouse and monitor. I then proceeded to install the other software I needed using the command prompt on a remote terminal.
This machine has performed flawlessly for me over the past week and a half. Not only does it save space over a desktop, but it also saves money on electricity. If you assume (conservatively, based on my measurements above) that a desktop PC consumes an average of 50W, this setup saves 40W. That adds up to about 30KWh saved in a month. If electricity costs 10 cents per KWh, that is a savings of around $3 a month, or $36 a year.
A mini-PC such as this is too specialized to be just walk in and buy at retail stores like Walmart and Best Buy. It is available on Amazon, for around $200. If you are an Amazon Prime member, it probably makes the most sense to buy it there, so you can get it in two days. Actually, in my part of the US there is free one-day delivery for this item. In fact, I ordered this on Sunday evening and had it by noon on Monday. If you don’t have Amazon Prime, then eBay may be your best bet for purchasing this. Some computer specialty stores may also be able to custom-order it, but this would likely be the slowest option.
Disclosure: I am not associated with the manufacturer of this mini-PC, nor any of the retail outlets mentioned above. I am not being paid by anyone for this blog post – I simply wanted to share my findings and recommendations.