@Aabingunz 

Could be a number of things.

One would be the cable to the router. However, you are not clear in your problem description?

Aabingunz wrote

Hello Tp-Link Community

 

Can you please help me with my query?

 

I have a tp-link Archer C9 (US model). I got an ACT broadband connection (INDIA), with a plan of 150 Mbps. When I am directly connected to the direct internet cable, I get around 150 Mbps as expected. However, once I connect back the Internet cable to my router's WAN port and use the 5G wi-fi, the internet speed does not exceed 100 Mbps.

 

I have tried different channels as well as auto channel selection and channel width but no improvement.

 

Is there a hardware fault or am I missing something? I even tried resetting the router but no luck.

 

Please help me with your insights on what could be the problem and how do I resolve this.

 

Thanks

Abhishek

I highlighted 2 parts in bold.

The first you are using an ETHERNET cable from the ACT to the PC and you get full speed.

The 2nd you are using the Wifi of the Router..

The 2nd one is the problem, and first question is the SAME cable used to go to the PC connected to ther Router. I assume it is, but want to ask.

Also, are you testing speed using the same app or web site?

Are you SURE you are connect to the 5Ghz? If you are using SMART CONNECT, you mignt not be.

What is the Wireless device by the way?

@IrvSp Thank you for your time in providing your insights. Yes, (reply to bold part) your understanding is correct. To answer your questions.

IrvSp wrote

@Aabingunz 

 

Could be a number of things.

 

One would be the cable to the router. However, you are not clear in your problem description?

 

Aabingunz wrote

Hello Tp-Link Community

 

Can you please help me with my query?

 

I have a tp-link Archer C9 (US model). I got an ACT broadband connection (INDIA), with a plan of 150 Mbps. When I am directly connected to the direct internet cable, I get around 150 Mbps as expected. However, once I connect back the Internet cable to my router's WAN port and use the 5G wi-fi, the internet speed does not exceed 100 Mbps.

 

I have tried different channels as well as auto channel selection and channel width but no improvement.

 

Is there a hardware fault or am I missing something? I even tried resetting the router but no luck.

 

Please help me with your insights on what could be the problem and how do I resolve this.

 

Thanks

Abhishek

 

I highlighted 2 parts in bold.

 

The first you are using an ETHERNET cable from the ACT to the PC and you get full speed.

 

The 2nd you are using the Wifi of the Router..

 

The 2nd one is the problem, and first question is the SAME cable used to go to the PC connected to ther Router. I assume it is, but want to ask.

 

Also, are you testing speed using the same app or web site?

 

Are you SURE you are connect to the 5Ghz? If you are using SMART CONNECT, you mignt not be.

 

What is the Wireless device by the way?

1. Also, are you testing speed using the same app or web site?

I used both speedtest.net and fast.com websites to measure the speed. Please check the below images.

2. Are you SURE you are connect to the 5Ghz? If you are using SMART CONNECT, you mignt not be.

There is no SMART CONNECT, I am connected to 5Ghz WiFi connection. Please check the below images.

3. What is the Wireless device by the way? 

I have tried 2 Laptops, 1 android, and 1 iPhone. Please check the below images.

Let me know if you require any further information to troubleshoot and help with this issue.

Problem Description diagram

Direct Ethernet cable from ACT Fibernet ISP as shown in above screenshot (1)

TP-link Archer C9 configuration of 5Ghz wifi network

Connected to 5Ghz Wifi network on a Windows 10 PRO

@Aabingunz 

Thanks, a lot of good info there.

One thing missing though, if you were to connect via Ethernet to the router, what is the speed then? That might help pin-point the possible problem.

Right now, I'm thinking a QoS setting. See Manual page on that, https://static.tp-link.com/Archer%20C9(US)_V3_User%20Guide.pdf#p52, there is a BANDWIDTH setting there, it might be set to 100Mbps even.

If QoS is on, turn it off and test.

I am not familiar with your ISP and the connection? If it is a MODEM, normally when switching devices, both modem and device needs to be turned off. Then connect the devices and power on the modem first, then the device after the modem is fully up. You can't just 'hot plug' the devices, the modems generally 'remember' who they were connected to and don't work well with another device. Powering off 'removes' that memory.

Your picture (really nice and clear) shows 2 cables, one to the laptop and one to the router. I assume they are the same one? If not, that could be the problem, one is not a CAT 5 or higher and can only handle 100Mbps.

The LAST thing I'd try, CLONE the Router to the SAME MAC address of the LAPTOP. You do that on the GUI's Advanced page, under NETWORK, INTERNET, at the bottom. That will make the Router look like the LAPTOP to the ISP connection. Test the speed then.

If it STILL fails, I'd contact TP-Link Support (I am an end-user like you are) and see if they can tell what is going on.

@IrvSp  I have tried with both QOS enabled and disabled but it does not change anything w.r.t connection speed. So I switched back to QOS enabled and there it is 1000 Mbps bandwidth limit.

Also, when I connect from 1 of the available 4 Ethernet ports from the router the speed does not change, it remains under 100 Mbps.

I have also mailed Tplink support for help. Hoping to get an answer. Thank you for your help.