For those of you interested in re-purposing your old mini-PC as an OpenWrt router, read on.
Main idea: Your existing wireless routers become dumb APs (no DHCP server, no DNS). Your old mini-PC becomes the actual router, and since even pretty old mini-PCs will easily have at least a couple of times the processing power of modern routers as well as a lot more memory and disk space, you can run OpenWrt x86/64 on it and turn it into a powerhouse running all kinds of useful "stuff".
Any old mini-PC will do. Even a crappy old Intel i5-4590T works wonders. AMD works well too. Minimally, it must have a 1000 Mbps RJ-45 Ethernet Port, at least one USB 3.0 port, and another USB port to connect your keyboard. HDMI is also required to connect to a display.
Side note: you would generally want a build that consumes minimal power at idle. I would say 4W - 6W is ideal. More is fine of course but do work out your monthly cost accordingly.
(Interesting note: I have even gotten this to work with old laptops since many of them fit the above requirements, plus they have their own display. The power consumption is surprisingly low at idle as well because they are designed to not drain laptop batteries quickly, so it actually works well when you run it off AC power. Only thing is that laptops are usually not designed to be turned on 24/7 and tends to generate more heat. Your mileage will vary.)
I suggest using the built in RJ-45 Ethernet Port as LAN, and a UGreen Ethernet Adapter 2500Mbps USB-C/A to RJ45 (for example:
https://shopee.sg/product/859347743/27579031991) as WAN. Cheaper adapters tend to have dodgier builds whereas I have found the above UGreen adapter to be super solid. It only costs about SGD 20 so don't stinge as you want your network connection to be rock solid. For the above adapter, you will need to do "opkg update && opkg install kmod-usb-net-rtl8152". You will then see the following at bootup: r8152 x-x:x.x: load rtl8156b-2 v3 10/20/23 successfully
And there you have it. Once your hardware is sorted, you simply install OpenWrt x86/64 into your hard disk and you're good to go. There's a lot you can do with it and it would be the most powerful consumer router that you can have at an extremely low cost.
Once you have installed the latest OpenWrt 24.10.2 on it, be sure to install owut: "opkg update && opkg install owut". This makes future updates as easy as "owut upgrade". It builds a custom firmware for you based on your existing packages, downloads it, checks the checksum, and then installs the new firmware which will result in a reboot. This takes about five minutes in total. Makes future updates so much easier.
Here is the official OpenWrt x86 guide to get you started:
https://openwrt.org/docs/guide-user/installation/openwrt_x86
Signing off for now. Open to questions and for experts to weigh in.
