What's new

Asus RT-AC87U: 5mhz weak performance

  • 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!

elgreco29

Regular Contributor
Hi,

since yesterday i´m on ac87u (before ac66u) with the newest merlin firmware. I´m impressed by the 2,5ghz performance, on the other side the 5ghz performance is very weak (2,5 mb/s with a htc one m7 and a samsung galaxy note 2014). I tried different channels and 20, 40, and 80mhz, but it´s not getting better. Any conclusions what to do? I read something about the qualcomm chipset. Ist this the problem?

Thanks in advance.
 
Distance? Obstacles? The 5 GHz band has a much shorter range, and will be more affected by obstacles than the 2.4 GHz band.

The RT-AC87U 5 GHz uses a Quantenna chipset (not Qualcomm).
 
for me 5GHz work perfect. I use "AC" and "n" devices.
 
My 5Ghz has been rock solid for quite some time on my RT-ac87. The AC87 did have issues on that band--they where a headache, early on, but firmware seems to have fixed it for me. What firmware are you running? If is recent, have you factory reset your settings recently? (Sometimes things that are carried forward cause issues I haven't had issues with recent firmware.)

First I would try going on my device, clicking on the 5G network, then tell it to forget the connection. After that reconnect and see if it works.

I would reccomend
-restoring to factory defaults (this changes the settings--doesn't change firmware)
-installing new firmware.

I personally go through and screenshot any settings that I don't know by memory to make setup faster.

Some users also have problems with beamforming and MIMO. (Wifi-professional-select 5ghz from the top pull down menu.). Personally. I dont have issues with them on 5G-- I leave them on. However, if you still have issues after a restore and update, try turning off universal beam forming--if you still have an issue, try turning off the others.

I use 149 with 80 MHz channels. He performance is great. My neighbors are far enough away that I don't have much issue with interference. However, if you live in a more densely populated area (you can pick up a bunch of your neighbors wifi throughout your house), you might try smaller channel width. Also, if you load merlin's firmware, there is a site survey tab under wireless settings that lets you see what channels your neighbors are using--it maes it easier to set up something on a channel that they aren't using so you don't have the interference issues.

Another troubleshooting tool is under system logs-wireless, look at the SNR for 5 ghz. That tells you how much stronger your signal is as compared to noise/interfearence. And finally, it tells you how strong the signal is to your device and the link speed for to tx (send) and rx (recieve).
 
Last edited:
My 5Ghz has been rock solid for quite some time on my RT-ac87.
Some users also have problems with beamforming and MIMO. (Wifi-professional-select 5ghz from the top pull down menu.). Personally. I dont have issues with them on 5G-- I leave them on.

I use 149 with 80 MHz channels.

Excellent post from bepotrumpet; we have the same settings (80 MHz, Channel 149) with the same very good results on our rt ac87r, repurposed as an access point wired back to the rt ac3200 serving as the main router. We have Apple series 7 phones, Samsung Galaxy 5, 8, and Note 4 phones and several differing Amazon readers and Dell laptops.

We have Gigabit service from the ISP and generally see around 350+ Mbps from the 87r (a similarly configured Asus rt ac68P amazingly produces a little more speed!)

Now, at one time we did have an issue where the 87r would do no more than 94 Mpbs; that turned out simply to be a Cat5 cable that was either loose at the wall connection or somehow had failed. New cable, fixed. After changing all the settings, multiple firmware version installs, full resets, calls to Asus tech support, and hair pulling, and all is good again.

Work your way through bepotrumpet's suggestions and make certain all your connections are solid.

I think whatever issues Asus may be had originally with the rt ac87r (or 87u same router) and 5Ghz have been resolved at the router level (I suspect client issues remain)

Good luck!
 
Last edited:
Hi,

To fully reset your router, you should
  • always do a factory reset after the firmware update AND reconfigure the router manually (or use John's backup/restore tool) - never restore from the router GUI if you change the firmware!
  • turn off the router to reset the chips (on reboot it's not sure that the chips are fully reset).
  • do not touch the wireless professional settings unless you really know what you are doing! Here you find the details.
Now you can test the 5 GHz networking again... ;)
 
Trouble with 5GHz.
It has not worked at all.
Installed 380.68 today and it work fine but not the 5GHz. Shift reload and reboot was done.

The 2.4GHz LAN MAC address and the Wireless 2.4GHZ MAC address are the same.
The 5GHz MAC address is the same, but the Wireless 5GHz MAC address ends with a different number.

Yes, I have tried to change the last number.

Regards
 

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!

Staff online

Top