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Paying for 1GB but not even getting half the speed

Slugspeed
New Poster

Paying for 1GB but not even getting half the speed

So, since the instal was completed I’ve never been able to attain speeds over 540mbs. It’s been Fast forward about 7 months and still no change. Decided to purchase the NETGEAR CM1000 modem as well as a few EERO routers and that still did not help. Why can’t this issue be resolved? I contacted Comcast/xfinity tech support and 2 tech visits later and still no better speeds. The next recommended action is to replace my rental equipment and see what happens. Shouldn’t the new modem that I mentioned previously be better or considered a replacement? If this can be escalated to another level on maintenance or engineer status I think it might help with what I have. Can anyone help? Where is my guru?
EG
Expert

Re: Paying for 1GB but not even getting half the speed

For a test, what speed do you get with a computer hardwired directly to the CM1000 cable modem (no router in the mix) ?



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Slugspeed
New Poster

Re: Paying for 1GB but not even getting half the speed

I want to say it was around 350GB.
bvwhitney
Frequent Visitor

Re: Paying for 1GB but not even getting half the speed

There are several factors that determine speed when above about 300Mbps.   I chased the same issue for days and found the bigest issue is if the test site is using IPv4 or IPv6.  I found my router can only acheive about 350Mbps using IPv6, but can get 950Mbps using IPv4.  The older Xfinity speed test had an option to set which IP version to use, but defaulted to IPv6.  I have since switched to DSLreports speed test which allows selection of several test settings in the advanced section.  To get the full 1Gbps I would use IPv4 and search for a very fast router.  Most consumer routers will not achieve 1G using IPv6.  I just bought a commercial router but I haven't put it online yet as runs Linux and uses command line syntax for settings.  This class of router usually does not include WiFi so you will need a WiFi router as well.  As stated above, everything must be wired with good ethernet cables.

 

UPDATE:

I see the new Xfinity speed test now allows selection of test server and IP version.  Another thing I found was if your computer is attached to your network through switche(s), the economical swithes will slow your speed as well.  I plugged my computer directly into my modem to get full spped when I upgraded to 1G.  I bought a managed, full duplex 16 port switch to replace my cascaded $15 5 port switches.  Now everything is home run directly to the 16 port switch.  This also made a huge different during my 1G testing.

 

Wrights128
New Poster

Re: Paying for 1GB but not even getting half the speed

Just to add a little more info to this thread.   I have 1Gb service.  I use a DOCIS 3.1 modem and an Orbi mesh router system.  My desktop PC is on the wire.  Modem -> Router-> Switch -> Desktop.  Up until about a month ago, I was seeing between 970Mbs and 1.0 Gb on the speed test.   On WiFi (laptop) getting about 550 Mbs, probably due to back chanenl communication over the mesh system, etc.  Very acceptable.

 

About a month or two, ago, the speed test dropped to between 490Mbs and 510Mbs (on the wire) and has remained there.  No other changes to my network have been made.  It seems quite likely to me that Comcast has re-distributed bandwidth and/or throttled speed,  perhaps due to increased demand during the lockdow when more folks are not in the office (i.e. they are online, at home). 

 

I've tested this pretty thoroughly, and I'd  love to hear some other feedback or explanation.  Right now, I can't think of one...

MaryJane7
New Poster

Re: Paying for 1GB but not even getting half the speed

You’re lucky! I upgraded to the 1GB and barely get 100mbps. I’m currently only getting 40mbps on my PS4 and it’s hard-wired. Been going back and forth with tech support since May! I changed out gateways to the “best they have”, a tech has been out and says “everything is good”. So frustrating. I’m about to tell them to just put it back on the 300 Blast since they’re obviously not trying to fix it.
Sledfpv
New Poster

Re: Paying for 1GB but not even getting half the speed

I am having the same issue with slow download speeds. I thought it was my router going bad as it was powering off and on by itself. I upgraded to the Amplifi Alien and my wifi speeds went from 275 to around 360 on my phone, but still not what they should be. When I run the speed test built into the router it's about 540, and I plugged my work laptop in to the router and was able to get 620 one time... I also have a Netgear CM1200 modem. I called them today to try and talk to a human but the automated system just forced me to reboot my modem even though I had done that like 5 times and said they would call me back after it was finished but never did...
jlavaseur
Valued Contributor

Re: Paying for 1GB but not even getting half the speed

I get the 1 gig speeds with no problem with the Xb6 gateway, I am curious if anyone checked the settings on their network cards, configured wrong and you won't get the 1 gig speeds, also are you using a Dell computer? They install a program called smartbyte that throttles your download speeds to about half of what is expected, I also experimented with the different router settings that I was able to change, some say they are grayed out, but mine aren't and I was able to dial in optimum speeds, just my thoughts