netinstall ethernet port of hap ax3?

Hi all,
I have a hap ax3, I’d like to use netinstall to install v6. I downloaded correct versions of netinstall and routerOS for it.
After I launch netinstall as administrator in windows 10, plugged cable to port 1, press reset button then plug in power,
after pressing reset button for almost 1 minute, nothing happens. The device never showed up in netinstall window.

Wonder which port is for netinstall? I couldn’t find info from Microtik manual. Is there sth I didn’t do right?
Thanks.

Did you follow this wiki step by step?
https://wiki.mikrotik.com/wiki/Manual:Netinstall

As far as I know all ax devices are v7. Any reason for wanting to run v6?

It’s impossible to run V6 on AX3.
You can not go below factory version and for all AX devices that’s V7 (here at home I see 7.5 on AX3).

Added argument: wifi drivers needed for AX3 only run on V7.

Yes, I did follow all steps on that page. Double-checked.
It’s because I feel v6 is more user-friendly than v7 and easier to configure. That’s just me.
If can’t downgrade on ax3, that’s fine. I’ll stick with v7, I believe it’s v7.15.3. I don’t see v7.5 on routeros download page.

On v7 it’s generally safest to stick to latest stable release. Indeed there are some problems with newest versions on certain devices and then it’s wise to run slightly older (e.g. some people have some problems with 7.15.x while running 7.14x is fine). But 7.5 is pretty old and since then, many bug fixes and enhacements were implemented. Among other things many were on wifi-qcom driver (which is required on your device).