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Gigabit Service running at 500mbps - HELP

markprenaj
New Poster

Gigabit Service running at 500mbps - HELP

Hey Guys,

 

I just upgraded to xfinitys Gig service last week and my speeds are very inconsistant!

 

If I run a speed test on xfinity's website I get 500mbps-980mbps, but its very random, and rarely does it hit 900mbps+

 

When I run tests through another website I dont ever go past 500mbps. (I get they go through other servers and whatnot, but that shouldnt effect my speed by half of what I'm paying for!)

 

I'm currently using a CM1000v2 Netgear Modem (Docsis 3.1) connected to my Netgear Nighthawk R8000P with Cat7 network cables.

 

Below are my cable modem signal strengths (i've called xfinity twice now and nothing has changed) 

 

Is there anything wrong with these numbers? 

 

Starting Frequency

<tabindex=-1>Startup Procedure</tabindex=-1>
Procedure Status Comment
Acquire Downstream Channel 507000000 Hz Locked
Connectivity State OK Operational
Boot State OK Operational
Security Enable BPI+
IP Provisioning Mode Honor MDD IPv6 only

<tabindex=-1>Downstream Bonded Channels</tabindex=-1>
Channel Lock Status Modulation Channel ID Frequency Power SNR / MER Unerrored Codewords Correctable Codewords Uncorrectable Codewords
1 Locked QAM256 5 507000000 Hz -0.5 dBmV 39.5 dB 105731185 0 0
2 Locked QAM256 1 477000000 Hz -1.4 dBmV 39.5 dB 104839181 0 0
3 Locked QAM256 2 483000000 Hz -0.9 dBmV 39.6 dB 104843188 0 0
4 Locked QAM256 3 489000000 Hz -0.5 dBmV 39.8 dB 104847026 0 0
5 Locked QAM256 4 495000000 Hz -0.5 dBmV 39.8 dB 104850423 0 0
6 Locked QAM256 6 513000000 Hz -0.9 dBmV 39.3 dB 104853886 0 0
7 Locked QAM256 7 519000000 Hz -0.6 dBmV 39.6 dB 104858080 0 0
8 Locked QAM256 8 525000000 Hz -1.0 dBmV 39.5 dB 104861932 0 0
9 Locked QAM256 9 531000000 Hz -0.6 dBmV 39.3 dB 104865648 0 0
10 Locked QAM256 10 537000000 Hz 0.4 dBmV 39.4 dB 104869061 0 0
11 Locked QAM256 11 543000000 Hz -0.1 dBmV 39.5 dB 104873004 0 0
12 Locked QAM256 12 549000000 Hz 0.8 dBmV 39.2 dB 104876843 0 0
13 Locked QAM256 13 555000000 Hz 0.9 dBmV 39.5 dB 104880432 0 0
14 Locked QAM256 14 561000000 Hz -0.4 dBmV 39.2 dB 104884002 0 0
15 Locked QAM256 15 567000000 Hz 0.6 dBmV 39.3 dB 104887895 0 0
16 Locked QAM256 16 573000000 Hz 1.1 dBmV 39.4 dB 104891638 0 0
17 Locked QAM256 17 579000000 Hz 0.3 dBmV 39.4 dB 104895148 0 0
18 Locked QAM256 18 585000000 Hz 0.0 dBmV 39.0 dB 104898806 0 0
19 Locked QAM256 19 591000000 Hz -1.1 dBmV 38.9 dB 104902677 0 0
20 Locked QAM256 20 597000000 Hz -0.7 dBmV 38.9 dB 104906529 0 0
21 Locked QAM256 21 603000000 Hz 0.4 dBmV 39.2 dB 104910241 0 0
22 Locked QAM256 22 609000000 Hz -0.7 dBmV 38.9 dB 104913727 0 0
23 Locked QAM256 23 615000000 Hz -1.2 dBmV 38.7 dB 104917828 0 0
24 Locked QAM256 25 453000000 Hz -2.0 dBmV 39.4 dB 104921446 0 0
25 Locked QAM256 34 459000000 Hz -1.3 dBmV 39.6 dB 104925109 0 0
26 Locked QAM256 35 465000000 Hz -1.3 dBmV 39.6 dB 104921469 0 0
27 Locked QAM256 36 471000000 Hz -1.3 dBmV 39.7 dB 104923014 0 0
28 Locked QAM256 38 429000000 Hz -2.1 dBmV 39.6 dB 104896777 0 0
29 Locked QAM256 39 435000000 Hz -2.0 dBmV 39.7 dB 104900715 0 0
30 Locked QAM256 40 441000000 Hz -1.4 dBmV 39.9 dB 104903866 0 0
31 Locked QAM256 41 447000000 Hz -1.8 dBmV 39.6 dB 104906081 0 0
32 Not Locked Unknown 0 0 Hz 0.0 dBmV 0.0 dB 0 0 0

<tabindex=-1>Upstream Bonded Channels</tabindex=-1>
Channel Lock Status Modulation Channel ID Frequency Power
1 Locked ATDMA 1 35800000 Hz 55.3 dBmV
2 Locked ATDMA 2 29400000 Hz 55.8 dBmV
3 Locked ATDMA 3 23000000 Hz 55.3 dBmV
4 Locked ATDMA 4 16600000 Hz 54.8 dBmV
5 Not Locked Unknown 0 0 Hz 0.0 dBmV
6 Not Locked Unknown 0 0 Hz 0.0 dBmV
7 Not Locked Unknown 0 0 Hz 0.0 dBmV
8 Not Locked Unknown 0 0 Hz 0.0 dBmV

<tabindex=-1>Downstream OFDM Channels</tabindex=-1>
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, 1, 2, 3 37 690000000 Hz -1.9 dBmV 34.5 dB 1228 ~ 2867 16452336 10334703 0
2 Not Locked 0 0 0 Hz -7.4 dBmV 0.0 dB 0 ~ 4095 0 0 0

<tabindex=-1>Upstream OFDMA Channels</tabindex=-1>
Channel Lock Status Modulation / Profile ID Channel ID Frequency Power
1 Not Locked Unknown 0 0 Hz 0 dBmV
2 Not Locked Unknown 0 0 Hz 0 dBmV

 

EG
Expert

Re: Gigabit Service running at 500mbps - HELP

The upstream power is too high / out of spec. 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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