@arunsethu 

Deco E4 has 100Mbit Ethernet ports.This is what limits speed of connection.

If you can, return E4 and get yourself set of Deco M4 or M5. 

If you can't return E4, buy additional single M5, make it Main Deco and connect E4 to it as Satellite Decos, wirelessly. 

@Alexandre. Thanks for your prompt reply. Is the 100Mbps limit apply even if I connect to the deco over wifi? Also these Decos are over 6 months old so dont think I can return them. if I buy M4 or M5 and connect my E4s wirelessly, will I be able to achieve the desired speed over 100Mbps? thank you

Arun

@arunsethu 

If you buy single unit M4 or M5, make it your Main Deco, and connect E4 to it wirelessly, the speed should increase. The bottleneck you have now is using E4 as Main Deco with its 100Mbps network port. Wirelessly, E4 can do much better.

M4 and M5 have gigabit ports, connecting either of them to Virgin hub by Ethernet cable will unlock your ISP speed. You must make gigabit port Deco your Main Deco.

E4 WiFi specs are up to 300Mbps for 2.4GHz and up to 867Mbps for 5Ghz. Connecting E4 wirelessly to Main Deco, assuming they are in good range with good WiFi signal from Main Deco, should also improve their Internet speed, increasing it above 100Mbps.

I don't think TP-Link sells M4 as single units, but it does M5. Look for good deals for M5 single unit, you might find them in the next 2-3 weeks, around New Year sales events.

@Alexandre. thanks much for your response. will try this and let you know how it goes. will keep an eye on Amazon for good M5 deals. cheers

@Alexandre. If I buy a M4 or M5 add-on unit which is sold separately, will that work? can I make it as the main unit by connecting to the hub and make all E4 as satellite?

@arunsethu 

Yes, you can make new M4/M5 your mesh Main Deco, without redoing the whole network. There is an option in Deco app to Set Main Deco. 

To make it work, connect M4/M5 by Ethernet cable to hub (hopefully you have an extra port on hub or can free one for configuration), configure it, make it Main Deco. After that, you can disconnnect E4 from the hub and move it elsewhere, it'll be your Satellite Deco, like all other E4 you have.

@Alexandre. I purchased a new M5 unit and made it as a main deco and made all my three E4s as satellites.  I have put my Virgin hub4 in modem mode and M5 as the router. While the speed I am getting is definitely higher than 90Mbps which I used to get from E4, its not the target speed I am looking for. I am on a 1Gbps connection but am getting only around 300-400 Mbps even with M5. I have tried multiple options still no luck. I got a new Cat 8 LAN cable and used it directly on my Hub4 router and tested the connection with a laptop while keeping all other devices disconnnected, still not more than 400 Mbps. When I spoke to Virgin they say as long as Samknows/realspeed site shows 1 Gbps download speed to the router they cant do anything. ANy thoughts? Does Virgin need to do anything on their end still? Appreciate your feedback. thanks

@arunsethu 

If you connect laptop by cable directly to Virgin hub4 that is running in modem mode, what speed are you getting in speedtest or from fast.com web site? 

Also, for clean test, I would suggest using cable that came with Deco M5 to run that test.

@Alexandre. So do you want me to use the cable that came with M5 to test the speed on my laptop when connected directly to the Virgin hub that is now acting as a modem? I thought when in modem mode only one of the 4 LAN ports will work which is already connected to the router. So do you want me to try with one of the other 3 ports? 

@arunsethu 

You will have to disconnect Deco from hub4 and connect laptop to the port used by Deco. The purpose of this test is to find what download speed would generic laptop/desktop device get from your ISP.

You can also just run "Test Internet Speed" from Deco app and it'll report you what you are actually getting from ISP, but it would be harder to convince Virgin it is their problem if you just use that test.

Yet, try that first - change nothing, except use cable that came with M5 to connect Main Deco to Virgin modem, and run "Test Internet Speed" from Deco app.

If you get less than you expect, then disconnect Main Deco, connect laptop to that same cable, run speedtest from laptop. If laptop also shows less than gigabit download speed, you'll have to talk to Virgin support. Either ask them send technicial to your house to show how gigabit download can be achieved, or you can sign for lower Internet tier, for example 500Mbps download. No point of paying for gigabit if you are not getting gigabit.