What's new

Brand new RT-AX86U, slow wired ports (more accurately, slow speedtests)

  • SNBForums Code of Conduct

    SNBForums is a community for everyone, no matter what their level of experience.

    Please be tolerant and patient of others, especially newcomers. We are all here to share and learn!

    The rules are simple: Be patient, be nice, be helpful or be gone!

whitey019

Regular Contributor
I have 1G/1G Verizon FIOS which has worked fine for several years with both an RT-AC68U and then an AC86U reaching 900+/900+ typically. I just installed an RT-AX86U with the latest firmware (45934) and my wired speeds are very inconsistent, 600-800up/200-500 down. If I plug the ONT directly into the computer I get 900/900. Also if I test with the speedtest app on the router itself I also get 900/900. I've gone back as far as firmware 42840 with the same results. Any ideas? My next step is to try another AX86U if I can find one locally.
 
I have 1G/1G Verizon FIOS which has worked fine for several years with both an RT-AC68U and then an AC86U reaching 900+/900+ typically. I just installed an RT-AX86U with the latest firmware (45934) and my wired speeds are very inconsistent, 600-800up/200-500 down. If I plug the ONT directly into the computer I get 900/900. Also if I test with the speedtest app on the router itself I also get 900/900. I've gone back as far as firmware 42840 with the same results. Any ideas? My next step is to try another AX86U if I can find one locally.

Try: https://www.snbforums.com/threads/how-do-i-get-full-speed-from-bt-fiber-1gb-broadband.76330/
 
I don't have to log into my ISP (Automatic IP) so those settings are not availalbe.
But you can still lower the MTU. Also try the 2.5 GB port connected to the ONT. Try another Ethernet cable btwn the ONT and router.
 
The MTU are not available unless I pick a WAN connection type of PPPoE. I've tried both the standard and 2.5G WAN ports. It's not the connection to the ONT, because the routers speed test performs fine, it's the wired LAN ports that have the problem. Also have tried a couple cables, but will see if I have more.
 
I ordered another RT-AX86U which is supposed to be here Tuesday. I will continue to try and troubleshoot this issue until then, so if anyone has any additional ideas, please let me know. Also, so far I have only used ASUS stock firmware. Is there any reason to believe Merlin's might impact this issue? What version of ASUS' firmware is Merlin's latest release based?
 
I seriously doubt replacing the router is going to solve the problem. You will find out but I will bet that replacing it is just spinning wheels. It's very likely a settings issue. Except for some Wifi customized settings use mostly default settings when you set it up. Enabling QoS or TrendMicro protection has been known to cause problems for some users. Curious... Does this bottleneck only effect wired Ethernet connections or does it also effect Wifi? You should be able to obtain at least 1Gbps connection throughput with line of sight same room Wifi connections to an AC or AX client.

You mentioned that you have Verizon Fios. Please detail the network topography and brand and models of the hardware you are using? Are you bi-passing the Verizon provided modem or ? If you were given the modem... What is the model of the modem? How is the modem set up? Did you try making any special adjustments in the modem for the router? Is it an all in one modem/router with Wifi built in?

Last time I set up with Verizon Fios I used their modem and I made special adjustments in their modem/router settings for the router. The one I set up was an all in one with DHCP, phone, TV output, etc.. It's running perfectly right now with an AX86U but it's doing "double NAT". It's not a 1Gbps service right now but it has been running rock solid for the past year.
 
Last edited:
SoCalReivews:

I have gone back at one point and factory rest the router, only had a basic initial configuration with only my wired computer connected and had the same result.
 
SoCalReivews:

I have gone back at one point and factory rest the router, only had a basic initial configuration with only my wired computer connected and had the same result.
I would steer clear of wasting your time believing it's a problem solved by resetting the router or replacing it. I've read about users in the past having problems with different ISPs connection with fiber and the ONT with many different models of routers. Unfortunately these kinds of issues are much easier for me to figure out on on-site. Unless this forum's users know every detail of your network topography and settings it can be difficult to determine the cause.

You could check with official Verizon support and the Verizon support forums for suggestions too. You're not the only person using an AX86U. It's one of the most popular Wifi 6 routers in the world right now. Checking for other Verizon FIOS user advice online is what I did before I set up the Asus router with Verizon FIOS. Asus official support might also have some settings advice.
 
Last edited:
Also seem to get better results with nperf.com.
Online speed tests can be notoriously unreliable. They involve much more than your local network and ISP connection. You're dealing with the entire internet connection and internet traffic as well. It's like me relying on file download/upload speeds to a company's busy remote web servers to determine how my router is performing. You can use it as a reference point but it's not information that can always be depended on as accurate.
 
I know, but they work when I plug the ONT directly into the computer.
I have had that same experience in the past with routers... You plug the computer direct in to the modem and it works perfectly and you get full speed but if you add the router it doesn't work or it's inconsistent. My issue was with Charter/Spectrum's servers not recognizing the new router. The Charter higher tier support tech had me go through a serious of sequential steps power cycling the devices to get their servers to recognize the new router. Once I did their procedures for a new router it always worked perfectly after that. I am not saying you have that problem but simply blaming source of the problem on the new router isn't a good way to debug.

You said that it worked at near full service speed for years with the AC68U and AC86U. That leads me to believe it's some kind of settings issue with the AX86U unless it's a hardware compatibility issue (which I doubt). I would also check to make sure you are updated with the latest drivers on the computer.
 
Last edited:
I played with the Asus Android app when I first got the AX86U and later found it had enabled QOS on the router without me realizing it. Just sayin double check settings like that just to be sure.
 
Im also having trouble with this. 1g/1g worked flawlessly on my AC3100. replaced it today with the AX5700/AX86U and I get 950Mbps down, but solidly 350Mbps up, wired. and the 350 is across multiple laptops. Strangely the Verizon link above works ok, 890/750 or something, but speed test app does not - nperf.com seems to get my 900 down and ~500 up. 800 down on AX, 222 up. set up as brand new, hand copied most of the settings from my 3100.
 
unacceptable considering my 3100 did 900/800
 

Attachments

  • Screen Shot 2021-12-27 at 8.01.26 PM.png
    Screen Shot 2021-12-27 at 8.01.26 PM.png
    18 KB · Views: 134
I have another router coming tomorrow, but I expect it to work the same way. I'm beginning to think Verizon is throttling speed tests. In my case less familiar tests work better and Verizon's test works fine. Either that or it is some kind of incompatibility with the AX86U and Fios.
 

Latest threads

Support SNBForums w/ Amazon

If you'd like to support SNBForums, just use this link and buy anything on Amazon. Thanks!

Sign Up For SNBForums Daily Digest

Get an update of what's new every day delivered to your mailbox. Sign up here!
Top