Poor performance on ASUS RT-AC65P

I recently bought ASUS RT-AC65P so I would able to use my 300mbps connection fully, as my older router was able to deliver only around 120mbps. On stock firmware I was seeing 300mpbs download and 400mbps upload on my laptop, but after flashing openwrt (OpenWrt SNAPSHOT, r13600-9a477b833a) the speeds dropped to around 120/200 on it.

I did nothing special in regards to configuration apart from trying to use SQM package but using it only made things worse (download dropped to around 80-90). I also think mu-mimo is not working as I loose wifi on my phone in my furthest room on openwrt whereas on stock firmware i got stable connection with around 250mbps (on 5Ghz).

Do you have any tips on making openwrt work at least so good as stock firmware? Do you know if mu-mimo is supported by openwrt on this router?

Really any tips or suggestions would be really appreciated. If any more specific info would be helpful please tell me and I will provide it.

Which version do u have? spanish or british? There are numerous reasons, check for redundant processes. If load causes problems its not due to the processor its due to firmware. Reinstall, it might fix it. MU-MIMO is supported.

Most importantly check the clock speed of your CPU! If its clocked down return it to 880mhz

Hi, thanks for your suggestions.

Those are the versions:
Architecture MediaTek MT7621 ver:1 eco:3
Firmware Version OpenWrt SNAPSHOT r13600-9a477b833a / LuCI Master git-20.168.58292-07aa28b

How can I check if this is spanish or british version?
Running ps lists 74 processes, load avarage right after running a speed test was: 0.05 0.10 0.04

I'm not able to find CPU clock speed anywhere but I doubt this being the issue as the cpu seems to be mostly idle, during speed test it was ~70% idle.

Do I have to do anything special to enable MU-MIMO? Does this affect the signal reception? I'm feeling that after reinstall the reception is much worse when I'm further from the router.

you need to edit hostapd file to enable MU-MIMO. Well 70% seems like a lot, perhaps it is a firmware problem. Devs are notified.

Thanks. I also had bad lags during steaming (described here: https://forum.openwrt.org/t/very-high-wifi-latency-on-asus-ac65p) and decided to go back to stock firmware. I think I will wait until this router is officially supported (will it?)

To check CPU speed you can use

root@OpenWrt:~# dmesg | grep MHz
[    0.000000] CPU Clock: 880MHz

In my case is 880MHz and I have very poor wifi download speed. Upload on 5Ghz is about 200Mbps (2/3 of ISP limit), but download between 20-60Mbps (ISP limit 1000Mbps, reachable via cable connection). Distance from router is lower than 50cm. I have almost last snapshot of oWRT OpenWrt SNAPSHOT r15666-8019c54d8a with luci manually installed. CPU idling during speedtest.

But range of WiFi is great, so it looks like software problem.

Where I can enable MIMO?