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Netgear CM500 - Upstream not channel bonding

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Netgear CM500 - Upstream not channel bonding

I'm having issues with my upload speeds when playing games and voice chat. 
I pay for the 600Mbps speed and I'm the only one in the household. 

Any help solving this issue is deeply appreciated. 

 

Netgear CM500 modem
Modem is connected to the line from the outside box. 
Modem is only 3 months old. 

Below is the connection log from the modem. 

Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 441000000 Hz Locked
Connectivity State OK Operational
Boot State OK Operational
Security Enabled BPI+
IP Provisioning Mode Honor MDD honorMdd(4)

 

Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables
1 Locked QAM256 1 441000000 Hz 11.8 dBmV 41.6 dB 0 0
2 Locked QAM256 2 453000000 Hz 11.9 dBmV 41.5 dB 0 0
3 Locked QAM256 3 459000000 Hz 12.1 dBmV 41.6 dB 0 0
4 Locked QAM256 4 465000000 Hz 12.3 dBmV 41.8 dB 0 0
5 Locked QAM256 5 471000000 Hz 12.3 dBmV 41.9 dB 0 0
6 Locked QAM256 6 477000000 Hz 12.5 dBmV 42 dB 0 0
7 Locked QAM256 7 483000000 Hz 12.6 dBmV 42.1 dB 0 0
8 Locked QAM256 8 489000000 Hz 12.7 dBmV 42.2 dB 0 0
9 Locked QAM256 9 495000000 Hz 12.8 dBmV 42.2 dB 0 0
10 Locked QAM256 10 501000000 Hz 12.9 dBmV 42.3 dB 0 0
11 Locked QAM256 11 507000000 Hz 12.8 dBmV 40.4 dB 0 0
12 Locked QAM256 12 513000000 Hz 12.9 dBmV 42.2 dB 0 0
13 Locked QAM256 13 519000000 Hz 13 dBmV 42.2 dB 0 0
14 Locked QAM256 14 525000000 Hz 12.9 dBmV 42 dB 0 0
15 Locked QAM256 15 531000000 Hz 12.9 dBmV 42.1 dB 0 0
16 Locked QAM256 16 537000000 Hz 13 dBmV 42 dB 0 0
 
Upstream Bonded Channels (Partial Service)
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 81 5120 Ksym/sec 36500000 Hz 44 dBmV
2 Not Locked Unknown 82 0 Ksym/sec 30100000 Hz 0.0 dBmV
3 Not Locked Unknown 83 0 Ksym/sec 23700000 Hz 0.0 dBmV
4 Not Locked Unknown 84 0 Ksym/sec 17300000 Hz 0.0 dBmV
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Gold Problem Solver

Re: Netgear CM500 - Upstream not channel bonding

  1. The CM500 is only rated by Comcast for use with plan download speeds "Up to 372 Mbps". See https://www.xfinity.com/support/devices/. Using devices with speed tiers for which they are not approved tends to produce unexpected results.
  2. Downstream power is a bit too high. See "Check your signal levels" in Connection Troubleshooting Tips.
  3. Only one upstream channel is locked. There should be at least three.

You need a modem appropriate for your speed tier, and you should probably have a premise tech out to take a look at signal levels and missing channels, if you can persuade Comcast to send one. Call them at the phone number on your bill or 1-800-Comcast, or use one of the options on https://www.xfinity.com/support/contact-us/.

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Re: Netgear CM500 - Upstream not channel bonding

The Modem is rated for speeds upwards to 680Mbps per Netgears site. 

I have contacted Xfinity's costumers service, and they escalted my case to a higher tier of tech support . They should be calling me tomorrow Monday 6/15/2020. 

What I'm trying to figure out is if it's the modem that is defective or is the signal being sent from Xfinity that is the issue. 

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Re: Netgear CM500 - Upstream not channel bonding


@Nickybuttons wrote: The Modem is rated for speeds upwards to 680Mbps per Netgears site. ...

That's a theoretical or lab-bench speed you'll never see in the real world. Manufacturer speed ratings don't matter, only the Comcast numbers do. That modem will never do 600 Mbps on their system.

 


... they escalted my case to a higher tier of tech support . They should be calling me tomorrow Monday 6/15/2020. ...

Chances are the problem is a mismatch between the modem and the speed tier, and/or local signal problems. It's not likely they'll be able to fix this remotely, unless dropping to a lower speed tier takes care of the problem. And that would still leave downstream power a bit on the high side.