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Netgear CM1100 speed and connectivity issues not getting Gig speed

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Netgear CM1100 speed and connectivity issues not getting Gig speed

I recently moved into a new townhome where Gig speed is offered.  I purchased a Netgear CM1100 that is listed as a support gig speed modem.  I have had service since 3/31/2020 and never once have I received more than 400-500mbs a second, and I experience random internet dropouts.  Things I've done to troubleshoot:

1) Factory Reset Modem

2) Tried several different Cat5e and Cat6 cables

3) Tried two different Microsoft Surface Pro 5 PC's along with a Desktop PC (all of which I have confirmed are supporting 1gbs under the ethernet adapter settings

4) I've tried connecting the modem at the wall outlet, at the feed line coming into the house, and at the feed line outside the house coming from the street

5) I've tried going through the troubleshooting on the xfinity app as well

 

Nothing has worked.  I have attached all the modem data pulled when connected at the wall outlet and the main line coming from the street outside.  I have tried going through the Xfinity chat but they are absolutely no help whatsoever.  Please someone, help me get this solved.

 

Here are the details when connecting to the main line coming in from the streetModem event log connected to main line.jpgModem info from main line.jpgModem status from main line page 1.jpgModem status from main line page 2.jpgModem status from main line page 3.jpgspeed tests connected to main line.jpg

 

Here are the details from the outlet in my home

Modem event log connected to outlet.jpgModem info at Outlet.jpgmodem speedtest at outlet.jpgModem status from outlet page 1.jpgModem status from outlet page 2.jpgModem status from outlet page 3.jpg

 

Here are the details showing my ethernet adapter can receive 1.0Gbps

Ethernet adapter status.jpg

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Expert

Re: Netgear CM1100 speed and connectivity issues not getting Gig speed

Can't see your pics. Since you are a new poster, they need to be approved by a Forum Admin. That could take some time. In the interim, you could try hosting them at one of those free third-party pic hosting sites like Imgur or Photobucket and post the link to them here.



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Re: Netgear CM1100 speed and connectivity issues not getting Gig speed

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Re: Netgear CM1100 speed and connectivity issues not getting Gig speed

Can someone please help now that I have the stats posted?

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Expert

Re: Netgear CM1100 speed and connectivity issues not getting Gig speed

Whoa, slow down. This isn't a real time support forum.

 

A few questions:

 

Did you run the speed test with the PCs directly connected to the modem without a router involved? Your OP was not clear.

Did you disable any security software or other network management apps prior to running the speed test? 

 

Also, here's a suggestion - Download the OOKLA Speedtest App for your desktop and see what you get for results (the app is better for gauging maximum capable speed as it's not encumbered by browser overhead and other factors). 


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Re: Netgear CM1100 speed and connectivity issues not getting Gig speed


@jkoenigseker wrote:

Can someone please help now that I have the stats posted?


Adding. In the last pic the upstream power is higher than the previous ones and is almost out of spec. Something intermittent is going on with the connection.

 

That can cause random disconnects, spontaneous re-booting of the modem, speed, packet loss, and latency problems.

In a self troubleshooting effort to try to obtain better connectivity / more wiggle room, check to see if there are there any excess/unneeded coax cable splitters in the line leading to the modem that can be eliminated/re-configured. Any splitters that remain should be high quality and cable rated for 5-1002 MHz, bi-directional, and no gold colored garbage types like GE, RadioShack, RCA, Philips, Leviton, Magnavox, and Rocketfish from big box stores like Home Depot, Lowes, Target, Wal-Mart etc. Splitters should be swapped with known to be good / new ones to test

If there aren't any unneeded splitters that can be eliminated and if your coax wiring setup can't be reconfigured so that there is a single two way splitter connected directly off of the drop from the street/pole with one port feeding the modem and the other port feeding the rest of the house/equipment with additional splits as needed, and you've checked all the wiring and fittings for integrity and tightness and refresh them by taking them apart then check for and clean off any corrosion / oxidation on the center wire and put them back together again, then perhaps it's best to book a tech visit to investigate and correct.



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Re: Netgear CM1100 speed and connectivity issues not getting Gig speed

I have no router involved at this time as I know that can cause issues potentially.  Everything was done connecting the Coax cable from the walll outlet, main feed inside the home, and the coax outside the home coming from the street.  The PC's were connected directly to the modem via two different Cat5E cables (one of which was the OEM cable from the modem box), along with three different C6 cables.  Everytime a different PC or cable was tried, both the Modem and PC were powercycled for the new connection.  The only splitter is one outside the home.  There is COAX coming from the street into a splitter, then two feed lines into the home come inside.  From there, the wall outlet Coax is coupled to one of the two main feed lines coming into the home.  The other feed has a termination connecter on it.  Both the splitter, coupler, and termination piece are all Xfinity's.  There are no other splittlers invovled.  I'll also add that I tested the other feed line from the splitter outside and the results were the exact same.  

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Re: Netgear CM1100 speed and connectivity issues not getting Gig speed

Adding to @EG if you compare your 2 levels outside vs inside, you have quite a bit of loss (even with a splitter). If the splitter is terminated on the other side, it serves no purpose get rid of it. Your modem’s stats should be more comparable within a dB or 2 from outside. With your cable it also sounds like you have 3 different sections of cable coupled/split which gives more chances of something failing.

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Re: Netgear CM1100 speed and connectivity issues not getting Gig speed

@CCAndrew 

Ok, so I should use a coupler from the outside line into the feed line coming into the house.  I can do that.  Any idea when connecting everything directly to the main coax line coming in from the street still didn't have any effect on my speeds?  I'm assuming the difference in levels at the wall outlet are giving me the random reboots, would I be correct in thinking that?

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Diamond Problem Solver

Re: Netgear CM1100 speed and connectivity issues not getting Gig speed

Could be something local, rate codes not correct/modem not provisioned properly. That’s why it’s important to eliminate and clean up what you can on the inside and possibly fix before the techs come out. Watch out for the gold couplers EG advised about above.Everyone here can only give you advice

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Re: Netgear CM1100 speed and connectivity issues not getting Gig speed

Thank you guys for the help and suggestions.  I'll use a coupler that Xfinity left instead of the splitter outside.  I keep trying to get a hold of someone from Xfinity to help but alas the only people I have gotten a hold of only offer the typical "have you tried turning it off and back on again".  I am very curious about whether it's provisioned properly but have yet to get a rep that even knows what that means.  Thanks again guys

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Re: Netgear CM1100 speed and connectivity issues not getting Gig speed

Today I removed the splitter and used a coupler from Xfinity to connect the main line from the street to the feed line coming into the house.  Here are the results:

 

[img]https://i.imgur.com/Yqg5OSi.jpg[/img]

[img]https://i.imgur.com/7CiHleF.jpg[/img]

[img]https://i.imgur.com/5uZNSq2.jpg[/img]

[img]https://i.imgur.com/tGpBOC7.jpg[/img]

 

My speed hasn't changed at all, I'm still getting only about 300-500mbps.  We'll see if this helps with the dropouts at least.  I was finally given a case number that a chat person gave me saying they escalated this.  Hopefully I'll hear back from them and eventually get this solved.