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Gigabit speeds not working

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Regular Visitor

Gigabit speeds not working

Hi,
I'm having an issue with not getting gigabit download speeds after upgrading to gigabit. I'm only getting about 400mbs on a hardwired connection with a cat 8 cable. I have called customer service multiple times and even had a tech come out but no one seems to be able to understand me or be able to fix the issue. Xfinity wants to put it back on me, which I don't understand.
I had blast pro (300mbs down, 10up) prior and in November 2019, I was getting horrible upload speeds (0.05). The tech replaced everything top to bottom in my house and what fixed it was increasing the power to box as the box did not have enough power to push the blast pro speeds out. I would assume this was primarily due to xfinity is fiber to the box and not fiber to the home. As more customers in my neighborhood are on xfinity the box did not have enough power to push the speeds needed.
In March 2020, I upgraded to gigabit and now I'm receiving the upload speeds of 42mbs wired and wireless but I'm only getting anywhere between 350-425mbs on a wired connection. I have done everything to fix this. Below is a quick snapshot.
1. Change my Ethernet cables from cat 5e to cat 8
2. Speeds are the same regardless of either connected through the modem or router
3. Speeds are the same through the rented modem and a gigabit modem certified for xfinity
4. Upgraded router to a wifi 6 router, same speeds
5. On router, changed all different types of settings: QOS etc.
5. speeds are consistent on wired and wireless
6. Speeds are the same on all devices, and devices are way over the minimum requirements of xfinity gigabit service (i.e. iphone 11 wireless, HP i7 64bit Windows OS with 32GB ram etc.)
7. and the list goes on....
The tech said that everything is fine and it was on my end. I had to push the tech to do anything further and after calling supervisor determined the next steps was to have a line engineer come out to check the line at the box. However, it has been a week and have not received a follow up call/notice. I called the tech and his supervisor and left a voicemail with both and have not heard back. Customer service is useless as they think increasing power to the box is resetting the modem. Customer service said they can’t do anything other than go through the troubleshooting steps and if they can’t fix it then they have to send out a tech.
Can anyone please help, as this does not make any sense. Being hardwired on a cat 8 cable I should be able to get gigabit speeds rather than blast pro speeds.
Thank you,
Shawn

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Expert

Re: Gigabit speeds not working

@saylorsm 

You failed to mention your modem specs.  That would be something that figures into the equation.


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Regular Visitor

Re: Gigabit speeds not working

Hi,

I tried on the following modems and routers:

1. Xfinity rented XB6-A (It is their latest model and I believe Xfinity calls it the Xfi)

2. Motorola Docsis 3.1 32x8 cable modem, model MB8600 (capable of 6,000Mbps via Ethernet bonding) Certified by Xfinity to work for gigabit.

Routers that I have tried:

1. Netgear Nighthawk X6 AC3200 Tri Band Model R8000

2. Asus AX11000 (Wifi 6 capable)

3. Netgear Orbi AC3000 model RBK50V

4. Netgear Orbi wifi 6 AX6000

All modems and routers received the exact same speeds no matter the configuration as noted above.

 

Thank you, 

Shawn 

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Official Employee

Re: Gigabit speeds not working

Hello and good morning saylorsm. It's frustrating to hear about your troubles with internet speed. We would like to help! First, I wanted to confirm that all of your equipment (beyond just the modem and router) are compatible. Please see this list here and then let me know: https://comca.st/3anfM0L.


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Regular Visitor

Re: Gigabit speeds not working

Hi,

@ComcastMorgan Sorry for the delayed response. I reviewed the minimum system requirements and I meet and far exceed them. Below are a few examples.

Xfinity minimum: CPU Intel Dual Core i5 or better with 8 GB RAM and 64 GB or larger SSD
my laptop: CPU Intel Dual Core i7 with 32 GB Ram and 250 GB SSD

Xfinity Minimum: Cat5e or Cat6 Ethernet Cable
My cables: Cat 8

Speed tests were ran on both Internet Explore and Chrome. Both had a maximum output of 500mbs hardwired with a cat8 cable into modem (Motorola MB8600). The average was about 420mbs.

What is interesting is that I'm not even getting the next tier above the blast pro (the 600mbs down) but I'm getting the gigabit upload (42mbs up). Xfinity is not fiber to the home (except for gigabit pro). The gigabit service is fiber to the box so as more users are home using the internet given COVID-19, I would assume the box does not have enough power to push high speeds little alone gigabit.

Thank you,
Shawn

 

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Official Employee

Re: Gigabit speeds not working

I appreciate you verifying all of that! If you can reply in the private message we have going with your last name, Shawn, I can take a look at a few things on this end. I want to check your modem's configuration file and some other diagnostics. Thanks!


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