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Gigabit internet speed issues

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Gigabit internet speed issues

Hi. We've recently upgraded from the 300Mb/s plan to the 1Gb/s option, and while we've seen a slight increase in speed (we're actually getting 300-400Mb/s now), we aren't getting anywhere near the rate we pay for.

 

I've followed most of the common troubleshooting guides, support has done 2 refreshes on their end (accompanied by me restarting our router/modem fairly often). I purchased an aftermarket modem (CM1150V) which is very much capable of handling the speed, and use a Netgear R700 for a router.

 

I have two computers connected via Ethernet that are able to transfer at roughly ~800-900Mb/s (through the router), so I am certain it is not a routing issue or problem with the computer itself. I have 32 locked downstream channels on the modem, however the event log generally has a lot of events and one of the downstream channels has a pretty poor correctable/uncorrectable ratio.

 

Again, to emphasize, I have already had multiple restarts (for several minutes) of both my modem and router, and have had Xfinity customer support perform refreshes on their end.

 

Attached is a snapshot of the modem information and some recent logs:

 

Frequency start Value
This field below allows you to modify the frequency the cable modem start with its scan during initialization and registration. Enter the new start frequency and restart the cable modem for it to take effect.
Starting Frequency
 
Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 675000000 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 37 675000000 Hz -0.9 dBmV 41.4 dB 0 0
2 Locked QAM256 9 507000000 Hz 0.4 dBmV 42.9 dB 3 0
3 Locked QAM256 10 513000000 Hz 0.3 dBmV 42.9 dB 5 0
4 Locked QAM256 11 519000000 Hz -0.3 dBmV 42.7 dB 1 0
5 Locked QAM256 12 525000000 Hz -0.2 dBmV 42.7 dB 1 0
6 Locked QAM256 13 531000000 Hz -1 dBmV 42.4 dB 1 0
7 Locked QAM256 14 537000000 Hz -0.7 dBmV 42.4 dB 1 0
8 Locked QAM256 15 543000000 Hz -1.1 dBmV 42.2 dB 1 0
9 Locked QAM256 16 549000000 Hz -1.2 dBmV 42.2 dB 1 0
10 Locked QAM256 17 555000000 Hz -0.3 dBmV 42.5 dB 2 0
11 Locked QAM256 18 561000000 Hz -0.9 dBmV 42.3 dB 1 0
12 Locked QAM256 19 567000000 Hz -0.3 dBmV 42.4 dB 1 0
13 Locked QAM256 20 573000000 Hz -0.7 dBmV 42.2 dB 1 0
14 Locked QAM256 21 579000000 Hz -0.8 dBmV 42.3 dB 0 0
15 Locked QAM256 22 585000000 Hz -0.4 dBmV 42.3 dB 1 0
16 Locked QAM256 23 591000000 Hz -1.3 dBmV 42.1 dB 0 0
17 Locked QAM256 24 597000000 Hz -0.8 dBmV 42.1 dB 0 0
18 Locked QAM256 25 603000000 Hz -1.4 dBmV 42 dB 0 0
19 Locked QAM256 26 609000000 Hz -1.7 dBmV 41.8 dB 0 0
20 Locked QAM256 27 615000000 Hz -1.5 dBmV 41.8 dB 0 0
21 Locked QAM256 28 621000000 Hz -2.2 dBmV 41.6 dB 0 0
22 Locked QAM256 29 627000000 Hz -1.4 dBmV 41.9 dB 0 0
23 Locked QAM256 30 633000000 Hz -2.3 dBmV 41.6 dB 18 15
24 Locked QAM256 31 639000000 Hz -1.8 dBmV 41.8 dB 5 0
25 Locked QAM256 32 645000000 Hz -1.7 dBmV 41.6 dB 0 0
26 Locked QAM256 33 651000000 Hz -2.1 dBmV 41.4 dB 0 0
27 Locked QAM256 34 657000000 Hz -1.1 dBmV 41.6 dB 0 0
28 Locked QAM256 35 663000000 Hz -1.7 dBmV 41.5 dB 0 0
29 Locked QAM256 36 669000000 Hz -0.9 dBmV 41.8 dB 0 0
30 Locked QAM256 38 681000000 Hz -1.2 dBmV 41.8 dB 0 0
31 Locked QAM256 39 687000000 Hz -0.3 dBmV 42 dB 0 0
32 Locked QAM256 40 693000000 Hz -1.2 dBmV 41.7 dB 0 0
 
Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 1 5120 Ksym/sec 36500000 Hz 45.5 dBmV
2 Locked ATDMA 2 5120 Ksym/sec 30100000 Hz 45.5 dBmV
3 Locked ATDMA 3 5120 Ksym/sec 23700000 Hz 45 dBmV
4 Locked ATDMA 4 5120 Ksym/sec 17300000 Hz 44.5 dBmV
5 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
6 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
7 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
8 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
 
Downstream OFDM Channels
Channel Lock
Status
Modulation /
Profile ID
Channel
ID
Frequency Power SNR /
MER
Active Subcarrier
Number Range
Unerrored
Codewords
Correctable
Codewords
Uncorrectable
Codewords
1 Locked 0 159 702000000 Hz 0.6 dBmV 42.2 dB 1126 ~ 2969 6177304372 225697 0
2 Not Locked 0 0 0 Hz 0 dBmV 0.0 dB 0 ~ 4095 0 0 0
 
Upstream OFDMA Channels
Channel Lock Status Modulation / Profile ID Channel ID Frequency Power
1 Not Locked 0 0 0 Hz 0 dBmV
2 Not Locked 0 0 0 Hz 0 dBmV
 
Current System Time:Tue Jun 30 10:02:31 2020
System Up Time:1 day 20:17:28

 


Time Priority Description
Mon Jun 29 11:34:40 2020 Warning (5) Dynamic Range Window violation
Mon Jun 29 11:34:40 2020 Warning (5) RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=***********************;CM-QOS=1.1;CM-VER=3.1;
Sun Jun 28 13:46:30 2020 Notice (6) CM-STATUS message sent. Event Type Code: 3; Chan ID: N/A; DSID: �; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=***********************;CMTS-MAC=***********************;CM-QOS=1.1;CM-VER=3.1;
Sun Jun 28 13:46:28 2020 Warning (5) Unicast DSID PSN startup error
Sun Jun 28 13:46:07 2020 Warning (5) Dynamic Range Window violation
Sun Jun 28 13:46:07 2020 Warning (5) RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=***********************;CMTS-MAC=***********************;CM-QOS=1.1;CM-VER=3.1;
Sun Jun 28 13:46:07 2020 Warning (5) Dynamic Range Window violation
Sun Jun 28 13:46:07 2020 Warning (5) RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=***********************;CMTS-MAC=***********************;CM-QOS=1.1;CM-VER=3.1;
Sun Jun 28 13:46:07 2020 Warning (5) Dynamic Range Window violation
Sun Jun 28 13:46:07 2020 Warning (5) RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=***********************;CMTS-MAC=***********************;CM-QOS=1.1;CM-VER=3.1;
Sun Jun 28 13:45:56 2020 Notice (6) TLV-11 - unrecognized OID;CM-MAC=***********************;CMTS-MAC=***********************;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Notice (6) Honoring MDD; IP provisioning mode = IPv6
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=***********************;CMTS-MAC=***********************;CM-QOS=1.1;CM-VER=3.1;

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New Poster

Re: Gigabit internet speed issues

are you on wifi? wifi speed will not come close to gig speed. fastest i have seen on wifi is around 500 Mbps. max download hardwired should be around 980 Mbps
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New Poster

Re: Gigabit internet speed issues

No, all of the computers I'm using to check the speed are connected via Ethernet. Further, I've tried downloading a file directly to the router (by logging into it) and I see similar speeds there.

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Expert

Re: Gigabit internet speed issues

For a test, do you get with a computer connected directly to the CM1150V modem (no router in the mix ) ?



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