Did you try this method?
I was looking at https://git.openwrt.org/?p=openwrt/openwrt.git;a=commit;h=e7c399bee677e9bac66e1bea697aefb8d828edfe, which seems incomplete, the 2nd radio's missing in the description, assuming wikidevi is correct.
Maximum possible WiFi speed (6000 Mbps) is higher on Xiaomi, but as far as I know, Asus routers have better WiFi coverage than Xiaomi routers.
I don’t have an Asus TUF AX4200 router. I’ll probably buy it if there is a way for me to install OpenWrt on it.
BTW, Asus RT-AX59U has the same CPU and possibly same/similar hardware.
Looks like Asus TUF-4200 has only 2x2 2.4 GHz and 3x3 5 GHz radios. Compared to Belkin RT3200 (mt7622, mt7915) or Dynalink DL-WRX36 (ath11k, ipq807x), both of which have 4x4 2.4 GHz and 4x4 5 GHz radios (I have both devices), is Asus TUF-4200 (mt7986) better when it comes to WiFi performance?
I haven't really tested the wireless radios yet and can't really compare them to anything. All I can say is that the 5GHz radio seems to have good coverage and the 2.4GHz radio not that great.
I saw you commenting Xiaomi AX6 topic. Could you please let me know how its coverage is in comparison to Asus TUF AX4200 when the same radio power is set?
I am evaluating whether to purchase this router to run OpenWRT.
I see that access to the serial console is required, but I cannot find any documentation on how to connect to it. I guess it might require some hardware mod, but I would like to see how to before I purchase the router. Please could anyone point me in the right direction?
Do you have a USB to serial adapter?
Yes I do. I just have to find it because I moved house recently 
Answering my own question I found this review:
with an image of the motherboard.
To the bottom right of the board there appear to be pins marked as VCC GND TX RX.
That must be the TTL serial. Can someone confirm?
How difficult is it to open the case without breaking it?
There is no serial header on the board but you can put the connector pins directly in the holes to make a connection.
Easy to open. 4 screws under the pads and then just pull apart.
I think TP-Link XDR6088/BPI-R3 would be better if you want to run openwrt, since they has 2x2.5G ports, BPI r3 even has 2G ram and pcie slot.
I can think of many not supported devices that are better...
The Asus is easier to get a hold of in the EU and when on offer is around 115€.
There are always better devices but availability and price are always a decision maker.
2 Likes
It cannot be found on either eBay or Amazon in Europe. Therefore it does not exist for me.
Thank you for confirm this. Now I have just to find a good offer and how to build an OpenWRT image for it. I assume it is in OpenWRT 22 master?
What hardware do I select? I cannot find mt7986.
Sorry. I thought that is already supported by openwrt mainline....
Since this is my first post here, I want to thank the developers for their great work.
I am planning to install Openwrt the next few days and just saw the last commit regarding TUF-AX4200:
mediatek: introduce KERNEL_LOADADDR to Device/Default template
"https://git.openwrt.org/?p=openwrt/openwrt.git;a=commit;h=e92b153e99a8019752b08c6ab0f7c17d9f08063e"
So I would like to ask if this commit has any impact on the installation process, or if the installation procedure mentioned in the first post in this thread is still valid?
This may be a stupid question, but I'm a clueless user afraid of breaking my new router.
I don't think that commit changes the howto instructions but I Could be wrong.
Just so you know, as long as you don't overwrite the bootloader it's almost impossible to perma brick this device.
Asus has a recovery tool to reflash stock image if anything goes wrong.
I have OpenWRT 22 master, but I cannot find the device.
Please could anyone let me know what to select for the following in .config to build an image for this router?
- Target System?
- Subtarget?
- Target Profile?