Router Performance of RT-AX86U - 386.7 vs latest stock


Occasional Visitor
tldr; Is anyone able to see router speedtests on the AX86U (386.7) >1gbps? And if so, any tips/suggestions?

Hey everyone,
I know I’ve seen some posts with questions about speed tests/router performance. But haven’t seen one that seems to get at the behavior I am seeing.

I have a 1.4 gbps plan from Comcast. I upgraded to an Arris S33 and AX86U about 5 months ago. Haven’t ever been able to get a Speedtest through the router to show anywhere near it. Max I end up see is roughly 750mbps.

Decided to flash back to stock (after reset) and check there. Get 1300mbps right away. So then I flash back to 386.7 (wps & factory reset) and am back to 750 mbps. Waited 20ish minutes and get the same.

I was thinking it was related to the scripts/usb drive/etc, but without any configuration (or other connected devices) I am not able to get a higher speed.

I’ve never enabled QOS, or AI Protect.

thank you.


Part of the Furniture
Asuswrt 49599 is newer code than the one used for Asuswrt-Merlin 386.7 base. Some differences are expected, you can't compare both. When you do speedtest, use a wired PC instead. Built-in GUI speedtest is not always accurate. It may be CPU limited on older code base and optimized in newer, but the real throughput to clients may be the same. If this is the case, it's only a cosmetic GUI difference.


Part of the Furniture
By the way, Wi-Fi performance in 49599 is much better than 49447 and similar code base 386.7 Asuswrt-Merlin. This much better:

Different users may have different experience, but 49599 was the firmware that made my AX86U the router I was expecting to get. The first firmware I tested was 49447 and then Asuswrt-Merlin 386.7 shortly after. I was thinking this particular AX86U unit is defective. :)
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Occasional Visitor
Thanks for the replies, and what you’ve found is very interesting.

I actually bought a 2nd thinking it was defective, but before unwrapping figured I should go back to stock and check. Seems like I’ll be returning that as it should behave the same.

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