290 mbps wifi, 340 wired

A First World, urban issue, I confess:

On my 300 Mbps service, wired I get 340 Mbps. On 5 Gigahertz AC Wi-Fi, it goes up to about 290, even if I’m right on top of it.

Changing channels doesn’t help either. Within my 80 MHz channel, there is one other Wi-Fi network. There are no channels with zero other networks. The Wispy folks said my 80 MHz channel reservation is fine on 5 gigahertz AC. That the protocol takes care of things properly and I’m not just hogging the channel from others.

So, have I hit my limit at 290 Mbps, concerning the networks around me? Is there anything else to tweak or try?

It’s not exactly the end of the world as it is. I’m just trying to maximize what I have.

It’s not worth taking too much time to fiddle with… It would also be nice to know whether it would not pay to ever upgrade my internet service to a higher bandwidth.

Thank you

Hello danielzr,

I’m trying to resolve this misthery with your help.

  1. What is the model of your access point ?
  2. What is the model of your computer used for this speed test (or wireless dongle) ?
  3. At what wifi speed are you connected during your Speed Test ?

Regards.

Rt-ac68u

A HP book 15 5th gen (i7 processor, not sure wifi chipset)

Pixel 3a
Both have similar wifi results.

Thanks!

Thanks for posting in the community!

Many things can affect WiFi throughput and max data rates. A good reference page to bookmark is the MCS Index here. Max data rate is heavily influenced by the # of spatial streams that your devices are capable of using. Chances are your client devices use 1 spatial stream and are therefore capped at about 390 or 433 Mbps in a perfect world. Remember that these max data rates are almost never achievable in a real world. Getting 290 Mbps wirelessly on a 300 Mbps capped plan is pretty ideal.

I discuss this in more detail and provide steps to troubleshoot further in this YouTube video here. Take a look and let me know if you have any other questions!

Hello danielzr,

Your devices have the following capabilities ;

  • RT-ac68u
    MCS 9
    3 spatial stream
    Short Guard Interval : yes
    Max Phy speed : 1 300 Mbit/s

  • Pixel 3a
    MCS 9
    2 spatial stream
    Short Guard Interval : no
    Max Phy speed : 780 Mbit/s

We can’t transfer data at a higher speed than of around 65% of the Physical Speed (wifi connection speed), because Wifi need administrative overhead, and this take some room.

Max Data transfer speed :

  • rt-ac68u : 1300*0.65=845 Mbit/s
  • Pixel 3a : 780*0.65=507 Mbit/s

I hope you have enought informations, if you want to upgrade your internet plan.

Regards

Hello casey,

Your Youtube video is very interesting, however i think you have forgot to take in account “the wifi overhead”.

Can you share the speed test with your MacBook Pro (MCS9 3ss) on your 945 data plan, for me your max data speed should be around 845 Mbit/s.

Regards.

Hi digtheweb,

Can you share the speed test with your MacBook Pro (MCS9 3ss) on your 945 data plan, for me your max data speed should be around 845 Mbit/s.

That is probably more accurate! My intent in the video was to illustrate that ISP backend speeds can also be the bottleneck in WiFi throughput tests. You’re correct that while the MCS Index says my MacBook Pro is capable of 1300 Mbps, in the real world I would be lucky to get more 65% of that.

Thank you for the detailed responses.

By the way, I just checked and on an HP ZBook 15U G6 I can get the full 320 some odd Mbps. So, the slight limitation seems to be on the client side.

Hi @danielzr,

thanks for this information.
Can you done once again a speed test with the G5 and G6 laptop and type the following command during these tests and share the result :

  • netsh wlan interface show

Below the results in my environment

image

I actually ran some more speed tests and the G3 vs G6 did about the same. They both sometimes reached 220.

Both had WiFi connection rates of 866.7.

Hello @daniezr,

Is it a typo when you said “They both sometimes reached 220”, or you meant 320 Mb ?

If you don’t experience the same speed variation with a wired laptop, you need to have more visibility to finger point the root cause, such your devices ar not the weak points.

Have you check these points :

  • SNR/SINR
  • Retry Rate
  • Co-Channel Interference
  • Adjacent-Channel Interference

Some tools like InSSIDer or Chanalyzer with a compatible device can help you to do this.

Regards

Thanks. Yes 320.
Yeah, there is one co channel on any 5ghz channel I can select, so this is probably the best I can do. Thanks

Hello @danielzr,

I’m glad you were able to identify the cause of this behavior.

Regards