@Kevin_Z 

AX-50 router, and very frustrated here. 

The router worked fine with the 100 mBps service from the ISP.  But then they upgraded their service, but the router output seems to be throttled to max out at 100 mBps. 

I've had the ISP technician out and he replaced the modem and the cable, but neither fixed the problem.  So I called TP-Link and spoke to one of their technicians.  He had me do lots of tests, but never offered any hypothesis or suggestions.  He mentioned that the firmware might need to be updated, but when I tried to do that, the router reported that it was current.  He suggested calling the ISP again, and when the technican came out for the second time, he replaced the cable (twice) and checked the speed at the output of both the ISP's modem and the AC50 router - 580 mBps out of the modem, but the router output was stuck at 95 mBps.  Similar speed on WiFI.

I've tried changing the negotiation speed to 1000mBps full duplex and rebooting the router - several times - but the WAN negotiation speed remains stuck at 100 mBps.

I reported the results of the ISP's second round of tests to TP-Link, and they came back with an offer to replace the modem.  But two hours later, they reneged on that offer because the warranty had expired.  I told them that was not a very customer-centric response,  and they came back with an offer to escalate the issue, but nothing further has happened.

From the number of posts in this thread, this seems to be a fairly common issue.  It's really surprising that TP-Link still doesn't have a clue what's causing it, nor do they have a fix.  The ISP's technician recommended buying a replacement router - something other than TP-Link. 

When otherwise the router is not gigabit, so its ethernet is limited to 100Mpbs, you could use the bridge function - not using ethernet, but wifi - and it will provide more than 100Mbps.

More info in: 
https://www.tp-link.com/us/support/faq/1083/
I would add as a last step to reconnect to router.

  @Kevin_Z 

Hi, When I login to my Archer C50 User face/menu is different from your screenshots and I cant find Internet under Network I cant find anything called NAT under any menu points.

 

  @Kevin_Z 

Hi i just bought an archer C50 W and I have called the ISP and they enabled full duplex mode on all lab ports yet with the C50 router I only get 91mbps download (says max 100 on ISPs router) and with my PS5 using the same cable and port I get download of 259 mbps the max download speed from my ISP is 300. 
 

serial number: 22334P5001769

ver. 6.0

any idea what I can do? Been trying for hours 

  @Pascal777 

Hi,

Have a look at the datasheet of the Archer C50 V6.0. https://static.tp-link.com/upload/product-overview/2023/202304/20230417/Archer%20C50(EU)6.0_Datasheet.pdf

It says "Ethernet Ports: 4*10/100 Mbps LAN Ports, 1*10/100 Mbps WAN Port".

  @Kevin_Z 

I tried to solve the issue through the solution suggested but the problem still persist. I have changed the negotiation speed (see screenshot).

I have also changed cables from cat5e to cat6 but this did not solve the issue. In the Ethernet interface of the GUI I still see that the connection in my LAN is 100mbps.
And it is the same even if I change the port from LAN1 to 2,3 or 4.

Please help me!

  @Rotella93 

Hi,

The "Internet Port Negotiation Speed Setting" is only for the "Internet Port", aka WAN port. It doesn't affect the LAN ports.

In order for TP-Link to assist you effectively you might want to post the exact model description of your TP-Link router (printed on the label on the underside) and also the brand and model of the client device you are trying to connect to the router at 1000 Mbps.

  @Kevin_Z 

I have 1Gbps service from my ISP and am consistently getting much slower speeds. If I connect my computer directly to the router LAN, I average approximately 105mbps download speed. When connecting through the WiFi, I am getting approximately 105mbps download VIA the 5GHz band and even slower on the 2.4GHz band. A tech from my ISP came on a service visit. The tech confirmed that I am getting 800-900mbps from the ISP provider VIA the ethernet port entering my home. This was confirmed VIA a direct ethernet connection to their client computer, as well as with connecting their own test router to the tech's client computer. I live in a condo and do not have an ISP-provided modem in my home, rather just the ethernet port coming through the wall.

1. Model number, hardware, and firmware version of your TP-Link Router.

- Model Archer AX 10 (US). This router is rated for 300Mbps on the 2.4GHz band and up to 1,201Mbps on the 5GHz band. 

- Firmware: 1.3.9 Build 20230728 Rel. 45716(5553)

- Hardware Version: Archer AX10 v1.20

2. What troubleshooting have you done, and what are the results (Screenshots)?

- I have followed all troubleshooting suggestions, including:

- Confirmed that the router Ethernet Status for the WAN is 1000mbps, and that LAN also shows 1000mpbs

- Setting the Internet Port Negotiation Speed Setting to 1000mbps Full Duplex

- Connected 3 separate CAT 5E cords from the router LAN to my client computer

- Upudated firmware for router

- Performed a factory reset of the router

- Turned the router off for ~15 minutes before turning on again

3. What are the devices that you are testing the LAN speed, and what are the models of the adapters?

 - Client computer used for testing is a Macbook Air M1, 2020, 16GB RAM, running Sonoma 14.2.1

 - Adapter for connecting ethernet to Macbook: nMOKiN 10-in-1, Model Number MOUC3903. This adapter is rated for 1000mbps ethernet connectivity per the manufacturer

4. When did you purchase the TP-Link router, and when did the issue begin to happen?

- Router was purchased in December of 2020.

- The issue was noted when we upgraded our internet to 1gpbs service in the Fall of 2022. I am only now addressing the problem.