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Xfinity speed issues

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bboncorr1

Occasional Visitor
A few months back I got a message saying they’d be updating the lines to 10G in the area. The line would be down for a few hours. Everything was working perfect before the line service. Since it came back up My equipment hasn’t been able to hit speeds over half of what I’m paying for. I’ve swapped out my Netgear nighthawk 2050 modem to a Arris S33. Both have a 2.5 Ethernet. Both are Comcast certified.

When I run speeds off the router (Asus AX11000) it’s getting half. When I run straight off the modem it’s half. Here’s the weird part, the speeds are half on the comcast website & comcast servers but on other servers like Starry it’s 1200-1400. Comcast is blaming my equipment (of course) even though I swapped out the modem. The tech came out and found the line was pulling 1.7 gig. He immediately blamed it on customer equipment. I went online to find a whole lot of people got that email and are having the same issues. Anyone have advice or recommendations?

Edit: since the replies don’t match what I’m asking I want to be even clearer, 10G speeds have nothing to do with what I asked. I’m paying for 1.2 gig but only seeing half that speed since the outside lines were upgraded. Again it has nothing to do with 10G speeds
 
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10Gbps ISP speeds are simply not possible with 2.5GbE equipment.

You need a 10GbE capable 'modem' to connect to the speeds you're paying for. And your PC or other client devices need that same port or greater to actually have a chance to hit those speeds (wired).
 
Xfinity 10G does not mean 10GbE WAN speed.
Xfinity 10G Network.png
 
10Gbps ISP speeds are simply not possible with 2.5GbE equipment.

You need a 10GbE capable 'modem' to connect to the speeds you're paying for. And your PC or other client devices need that same port or greater to actually have a chance to hit those speeds (wired).
That wasn’t the point of my post nor was it in any way the issue I discussed. I simply pointed out they updated the lines and used 10G as the reason. 10G has nothing to do with my stated issue. My issue was clearly stated to be not achieving half the speed I’m paying for when running tests off Xfinity servers.

I’m seeing 400-600 Mbps off the Xfinity servers while Starry servers are hitting the speeds I’m paying for (1200-1400 Mbps). I’m not trying to hit 10Gbps nor was it insinuated
 
What you didn't clearly say at first is half of WHAT.

If your modem qualifies (and the tech could have tested with his modem), and you are not getting the advertised speed, then the ISP has to explain it. Maybe someone here with knowledge of 10G technology might be able to explain how this could happen.

Have you tried downloading something (instead of a speed test)? Though, it might be difficult to find a server that will give you 1G (don't know, never had to test this myself).

Next, find another ISP?

(Just for info, my ISP, Mediacomb, will rent customers a modem for a day to test with, then get a refund for the rental. I had to do this to prove my equipment was not the issue.)
 
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I’m seeing 400-600 Mbps off the Xfinity servers while Starry servers are hitting the speeds I’m paying for (1200-1400 Mbps).

So you're getting your advertised speed, what is the problem? You want Comcast to upgrade their speed test servers for you or something? Not every speed test server is going to be able to handle the load 24x7x365 but by trying an alternate server you have proven your connection is fine.

But go ahead and yell at people in here for your own lack of info and confusion.
 
Again that has nothing to do with my post. Please read the full post. I clearly explained the full situation being I pay for 1.2 gig but only achieving half the speed SINCE THEY UPGRADED THE CABLE LINES USING 10G AS THE READON FOR THE UPGRADE.

You added 1.2 gig in an edit after that person replied. Clear as mud. I hope Xfinity charged you for the service calls.
 
Quick check to see if the wires are really hosed would be to go into the modem and see what downstream, upstream and S/N are.
I have the same plan you do and get the same speeds you do. However, at certain times, I can get a bit over 1 Gbs for a second or two. try meter.net for speed tests, it's very simple, no bs.
Another thing I found is with my router with 2.4Gbs WAN and LAN ports, if I use the LAN port, there's constant TV buffering into a Netgear switch and Shield. The rest of my stuff is 1Gbs, with the 1Gbs LAN port (and 2.4 WAN), all is good.
BTW, either port on the modem gives the same results, it's the downstream stuf f that may not play well.
 
Quick check to see if the wires are really hosed would be to go into the modem and see what downstream, upstream and S/N are.
I have the same plan you do and get the same speeds you do. However, at certain times, I can get a bit over 1 Gbs for a second or two. try meter.net for speed tests, it's very simple, no bs.
Another thing I found is with my router with 2.4Gbs WAN and LAN ports, if I use the LAN port, there's constant TV buffering into a Netgear switch and Shield. The rest of my stuff is 1Gbs, with the 1Gbs LAN port (and 2.4 WAN), all is good.
BTW, either port on the modem gives the same results, it's the downstream stuf f that may not play well.

OP is getting 1.2 to 1.4 gig, cables are fine.
 
So you're getting your advertised speed, what is the problem? You want Comcast to upgrade their speed test servers for you or something? Not every speed test server is going to be able to handle the load 24x7x365 but by trying an alternate server you have proven your connection is fine.

But go ahead and yell at people in here for your own lack of info and confusion.
you must be a higher power to hear tone within a text
 
You added 1.2 gig in an edit after that person replied. Clear as mud. I hope Xfinity charged you for the service calls.
I also put within the OP I was getting half the speed I paid for while 1200-1400 on another server. You seem like a spiteful child that thinks he’s reading into something correctly.
 
Quick check to see if the wires are really hosed would be to go into the modem and see what downstream, upstream and S/N are.
I have the same plan you do and get the same speeds you do. However, at certain times, I can get a bit over 1 Gbs for a second or two. try meter.net for speed tests, it's very simple, no bs.
Another thing I found is with my router with 2.4Gbs WAN and LAN ports, if I use the LAN port, there's constant TV buffering into a Netgear switch and Shield. The rest of my stuff is 1Gbs, with the 1Gbs LAN port (and 2.4 WAN), all is good.
BTW, either port on the modem gives the same results, it's the downstream stuf f that may not play well.
Changed out the wires 3x before running tests off other company servers. 2 certified and fluke tested Cat8 & 1 Cat 6E got same results. I also changed out the modem. The Arris is actually pulling in better speeds but it’s still only half on xfinity servers. I googled “Xfinity 10G update slower speeds” and found it’s happening nationally. People get a text or email saying the lines are being upgraded so service will go down. Then when service is back up it’s only half of the advertised speed.
 
Sorry @bboncorr1, you did not state what your paid-for ISP speeds were.

We're just people who like to help as much as they can. But we're not mind readers.

You need to state things explicitly and plainly. Without throwing random facts in there too.

I'm still not clear what your paid-for ISP speeds are.

I'm also not too clear on how you're testing for those speeds.

If you can use different servers and hit the speeds you expect, there is no issue.
 
@bboncorr1
#1 comcrap rule - It Is Always The Customer's Fault/Equipment As issue
Have you seen the comcast groups? People that had their area upgraded to faster up/down speeds, but not using isp equipment, comcrap has crippled the s33 to only 1/2 the upload upgrade speeds.
Those higher speeds "are not guaranteed" and "speeds are for a single device directly connected to their modem". I have been told some bizarre excuses from comcrap techs, some which defy physics/logic, as to why only lower speeds are achieved.
If you are having any issues with speed/quality, then have a comcrap tech inspect every single line and connection within your home to eliminate "you" being the issue. It took a month (June 2023) of multiple tech visits to eliminate my equipment as the issue, before they replaced the drop to my house, then two nodes on my block :rolleyes:
 
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When I run speeds off the router (Asus AX11000) it’s getting half. When I run straight off the modem it’s half. Here’s the weird part, the speeds are half on the comcast website & comcast servers but on other servers like Starry it’s 1200-1400. Comcast is blaming my equipment (of course) even though I swapped out the modem. The tech came out and found the line was pulling 1.7 gig. He immediately blamed it on customer equipment. I went online to find a whole lot of people got that email and are having the same issues. Anyone have advice or recommendations?

Try disabling QoS if it is enabled...

A quick note - chat here has gotten a bit spicy, please keep in mind that folks are happy to help, and being civil goes a long, long way...
 
@bboncorr1
#1 comcrap rule - It Is Always The Customer's Fault/Equipment As issue
Have you seen the comcast groups? People that had their area upgraded to faster up/down speeds, but not using isp equipment, comcrap has crippled the s33 to only 1/2 the upload upgrade speeds.
If you are having any issues with speed/quality, then have a comcrap tech inspect every single line and connection within your home to eliminate "you" being the issue. It took a month (June 2023) of multiple tech visits to eliminate my equipment as the issue, before they replaced the drop to my house, then two nodes on my block.


Good place to check for WAN issues is DSLReports - there is a dedicated forum for Comcast over there...

 
I figured out the problem. It was the line upgrade Xfinity just completed. 2000/120 just became available at my house after the upgrade to the lines. People all over are having this issue. They changed the frequencies and refuse to tell anyone about it. Basically if your modem isn’t approved by them for those frequencies they will not send a full signal. They have not approved any modems outside of theirs. I tried installing another 2 Arris S33 but Xfinity outright refused saying it’s not compatible now. This gives more strength to what an engineer explained online. After upgrades we are forced into their equipment or our equipment is limited.

I upgraded to the 2 gig and installed their modem into bridge mode. Everything went back to normal immediately.
 

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