Troubleshooting Deco LAN speed is capped at 100m/s
Occasionally we received some feedback about the slow LAN speed from Deco and the typical description would be: "my internet bandwidth is over 200/500m/s, but I only got about 100m/s from Deco". After troubleshooting with different users, the following causes are confirmed to be relevant.
(Note, if the model is Deco E4, you might get the wrong model since Deco E4 is up to 100m/s.)
- The Total bandwidth under QoS is set to be 100/100 m/s.
If you happen to have the same case, please change it to be 1000/1000 m/s.
Visit this guide to configure the QoS settings on the Deco.
- The WAN link speed is capped at 100m/s.
The WAN link speed might be caused by different reasons. The first one would be the Ethernet cable between the modem and main Deco. Please replace it with a good quality Cat5e or Cat6 cable.
If in any case, the issue persists after checking the first two conditions, we need more information to locate the problem:
1. Are all the Deco units capped at 100m/s or just one of the satellite units?
(if it is only one of the satellite units, the troubleshooting guide here might not be helpful, please refer to this link: Why is my satellite Deco unit not getting the same speed as the main Deco?)
2. Please connect a laptop via Ethernet cable to the main Deco and check the link speed on the laptop to verify whether it is 1G or 100m/s.
3. A picture of your network layout, such as
We would love to hear more comments from your experience!
Related Articles:
Troubleshooting: Slow Internet Speed with Deco Devices
Why is my satellite Deco unit not getting the same speed as the main Deco?
Why the actual wireless speed on my wireless device is lower than the speed result on the Deco APP?
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@TP-Link I'm having the same problem
P9's - 4 of them.
When I run the cables directly from the modem to the PCs I get full 1gbit.
Whenever I add the Deco P9 as the router, I'm capped at 100mbit for LAN but for some reason Wifi is much higher.
So there seems to be a problem with the LAN connection only.
Any suggestions?
QOS is at 1000mbit both for upload download.
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@TP-Enlace hello
i have an deco M4 connected to cat 6 and it appears to be 100mbps (orange light)
i need solutions
NOT AN E4
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Are you able to connect a laptop via the same cable to see how much speed you could get from the ISP modem?
By the way, is the "orange light" LED indicator on the switch?
Did your Deco M5 work in Access Point mode?
Thank you very much.
Best regards.
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I have a Deco X50 system set as Router connected to a Virginmedia Hub4 with 1GBps down and 100MBps up contract. In the Deco app I have QoS enabled.
If I set it to 1000MBps the speed test shows 200-300MBps.
However, if I set it to 999MBps I get 900-1000MBps!
Could this be the factor limiting the speed?
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Hello!
Currently, I am experiencing a speed limitation when using a wired connection with a Cat5e cable. When I connect my MacBook Pro to the router via cable, the maximum speed I can achieve is only 100 Mbps. However, when I use the Wi-Fi connection, the speed reaches 600 Mbps.
I have already followed all the suggested configurations and troubleshooting steps mentioned in the forum to address this issue. I have checked the router's specifications and confirmed that it has gigabit WAN/LAN ports. Furthermore, in the router's web interface, I have verified the "Negotiation Speed" of the Ethernet ports, and all of them are correctly set to 1000 Mbps.
I have also tested different Cat5e cables and attempted to connect my MacBook Pro to other available ports on the router, but the speed remains limited to 100 Mbps when connected via cable.
I kindly request your assistance in resolving this speed limitation issue. Please provide additional guidance or any solutions that may help rectify this matter.
Here are the relevant details for your analysis:
- Main router model: TP-Link Omada Gigabit Multi-WAN VPN Router.
- Connected Mesh router: TP-Link Mesh Deco X20 Whole Home
- When using Wi-Fi, the speed is approximately 600 Mbps.
- When using a Cat5e cable, the maximum speed is limited to 100 Mbps.
- All the settings suggested in the forum have been checked and applied.
- My device is a MacBook Pro.
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@TP-Link my Deco M4R (HW v1) only 100mbps. I tried my laptop to connect to the Main unit Port 1 or Port 2, the same result, my laptop card show 100mbps connection. use the same cable to connect to my home switch 1Gbps right away. the wifi connection from my laptop to M4r is 800mpbs, but due to the Ethernet to Internet is only 100mbps, the speed is capped as 100mps.
what wrong with the Ethernet port 1/2, why there are not Gigabit Ethernet?
Please help.
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@john2353 thank you. I did try Router mode with QOS settings as 900mbps, did not work.
AP mode does not work as well. this is physical NIC card issue, the M4 does not auto speed to 1000mbps, only 100mps to Cisco switch or even TPlink switch, or a Laptop direct connection, can not find anywhere on M4R to force it to speed as 1000mps?
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@GeorgeZ I have the exact problem with M4R.
Done exactly everything with QoS, different switches, direct connections and cables.
Ethernet ports on M4R slaves is only negotiated as 100mbit.
Why TP-link?
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Hi, welcome to the community.
It would be great if you could start a new thread here to tell me how you found out the Ethernet link speed on the satellite Deco M4 is capped at 100m/s.
The QOS usually doesn't restrict the speed of the satellite Deco.
Have you replaced the Ethernet cables? What does your network diagram/topology look like? Are Deco M4 units connected via an Ethernet cable, through a switch?
Best regards.
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