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Slow Gigabit Speed

New Poster

Slow Gigabit Speed

When I first upgraded to gigbit, I was getting the speeds expected.  Recently I'm topping off at about 300Mbps.  I own my equipment... a Arris Surfboard SB8200 and a Netgear XR500.  I've tried swapping cables, resetting the modem, and still have the same issue.  Called support and they said that they ran a check and I'm getting the speeds I should and it must be the modem.  Not sure where to go now.  Hardwired from the modem itself to the computer, I'm still only getting about 300M.  I've tried both ports on the modem as well.  Any help would be greatly appreciated, as I'd rather not resort to leasing one of their modems. The status page of the modem looks like:

Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 651000000 Hz Locked
Connectivity State OK Operational
Boot State OK Operational
Configuration File OK
Security Enabled BPI+
DOCSIS Network Access Enabled Allowed

Downstream Bonded Channels
Channel ID Lock Status Modulation Frequency Power SNR/MER Corrected Uncorrectables
31 Locked QAM256 651000000 Hz 9.0 dBmV 42.0 dB 0 0
1 Locked QAM256 453000000 Hz 8.0 dBmV 42.7 dB 0 0
2 Locked QAM256 459000000 Hz 7.9 dBmV 42.8 dB 0 0
3 Locked QAM256 465000000 Hz 8.2 dBmV 42.8 dB 0 0
4 Locked QAM256 471000000 Hz 7.7 dBmV 42.5 dB 0 0
5 Locked QAM256 477000000 Hz 7.5 dBmV 42.5 dB 0 0
6 Locked QAM256 483000000 Hz 7.2 dBmV 42.4 dB 0 0
7 Locked QAM256 489000000 Hz 7.0 dBmV 42.1 dB 0 0
8 Locked QAM256 495000000 Hz 6.6 dBmV 41.9 dB 0 0
9 Locked QAM256 519000000 Hz 6.7 dBmV 42.0 dB 0 0
10 Locked QAM256 525000000 Hz 6.6 dBmV 41.8 dB 0 0
11 Locked QAM256 531000000 Hz 6.2 dBmV 41.5 dB 0 0
12 Locked QAM256 537000000 Hz 6.1 dBmV 40.9 dB 0 0
13 Locked QAM256 543000000 Hz 5.2 dBmV 40.5 dB 0 0
14 Locked QAM256 549000000 Hz 4.1 dBmV 39.7 dB 0 0
15 Locked QAM256 555000000 Hz 3.0 dBmV 39.4 dB 0 0
16 Locked QAM256 561000000 Hz 3.8 dBmV 40.3 dB 0 0
17 Locked QAM256 567000000 Hz 5.9 dBmV 41.3 dB 0 0
18 Locked QAM256 573000000 Hz 7.0 dBmV 41.5 dB 0 0
19 Locked QAM256 579000000 Hz 7.8 dBmV 42.1 dB 0 0
20 Locked QAM256 585000000 Hz 8.4 dBmV 42.4 dB 0 0
21 Locked QAM256 591000000 Hz 8.3 dBmV 42.0 dB 0 0
22 Locked QAM256 597000000 Hz 8.6 dBmV 42.3 dB 0 0
23 Locked QAM256 603000000 Hz 8.7 dBmV 42.3 dB 0 0
24 Locked QAM256 609000000 Hz 8.6 dBmV 42.2 dB 0 0
25 Locked QAM256 615000000 Hz 8.7 dBmV 41.0 dB 0 0
26 Locked QAM256 621000000 Hz 8.7 dBmV 42.2 dB 0 0
27 Locked QAM256 627000000 Hz 8.4 dBmV 42.0 dB 0 0
28 Locked QAM256 633000000 Hz 8.6 dBmV 42.1 dB 0 0
29 Locked QAM256 639000000 Hz 8.5 dBmV 42.0 dB 0 0
30 Locked QAM256 645000000 Hz 8.9 dBmV 42.0 dB 0 0
32 Locked Other 690000000 Hz 9.4 dBmV 31.5 dB 43972708 0



Upstream Bonded Channels
Channel Channel ID Lock Status US Channel Type Frequency Width Power
1 4 Locked SC-QAM Upstream 36500000 Hz 6400000 Hz 44.0 dBmV
2 3 Locked SC-QAM Upstream 30100000 Hz 6400000 Hz 44.0 dBmV
3 2 Locked SC-QAM Upstream 23700000 Hz 6400000 Hz 45.0 dBmV



Current System Time: Mon Jul 15 17:10:03 2019

The event log shows:
Date Time Event ID Event Level Description
01/01/1970 00:00 2436694066 6 "Honoring MDD; IP provisioning mode = IPv6"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:01 68001101 3 "TFTP Request Retries exceeded, CM unable to register "
01/01/1970 00:01 68000500 3 "TFTP failed - Request sent - No Response;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
07/15/2019 16:33 2436694044 3 "Resetting the cable modem due to docsDevResetNow"
07/15/2019 16:06 82000500 3 "Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
07/15/2019 15:44 2436694044 3 "Resetting the cable modem due to docsDevResetNow"
07/15/2019 15:10 82000500 3 "Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
06/03/2019 07:20 82000400 3 "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
06/03/2019 07:20 84000500 3 "SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
06/03/2019 07:19 82000100 3 "No Maintenance Broadcasts for Ranging opportunities received - T2 time-out;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
06/03/2019 07:19 84000500 3 "SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
06/03/2019 07:19 82000100 3 "No Maintenance Broadcasts for Ranging opportunities received - T2 time-out;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
06/03/2019 07:19 84000500 3 "SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
06/03/2019 07:19 82000100 3 "No Maintenance Broadcasts for Ranging opportunities received - T2 time-out;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
06/03/2019 07:19 84000500 3 "SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
06/03/2019 07:19 82000100 3 "No Maintenance Broadcasts for Ranging opportunities received - T2 time-out;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
06/03/2019 07:19 84000500 3 "SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
06/03/2019 07:19 82000100 3 "No Maintenance Broadcasts for Ranging opportunities received - T2 time-out;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
06/03/2019 07:19 84000500 3 "SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
06/03/2019 07:19 82000100 3 "No Maintenance Broadcasts for Ranging opportunities received - T2 time-out;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
06/03/2019 07:19 84000500 3 "SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
06/03/2019 07:18 82000100 3 "No Maintenance Broadcasts for Ranging opportunities received - T2 time-out;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
06/03/2019 07:18 84000500 3 "SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
06/03/2019 07:18 84000500 3 "SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
06/03/2019 07:18 82000400 3 "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
06/03/2019 07:10 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
06/03/2019 07:10 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
06/03/2019 07:10 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
06/03/2019 07:10 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
06/01/2019 20:42 82000500 3 "Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
05/31/2019 14:16 82000500 3 "Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:03 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:03 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
04/25/2019 00:05 82000400 3 "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=2c:95:69:5c:ab:01;CMTS-MAC=00:01:5c:71:10:61;CM-QOS=1.1;CM-VER=3.1;"

Expert

Re: Slow Gigabit Speed

Those stats look o/k. Is this with a WiFi connection ? If so, for a test, what speed does a computer hardwired directly to the XR500 router with an ethernet cable get ?

 

As a second  test, what speed does a computer hardwired directly to the 8200 cable modem (no router in the mix) get ? You'll have to power cycle the 8200 when you make the change.



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New Poster

Re: Slow Gigabit Speed

No, with the modem hardwired to the computer directly, I'm only getting about 300Mbps.  When connected to the router, it's the same.

Silver Problem Solver

Re: Slow Gigabit Speed


@downindm wrote:

No, with the modem hardwired to the computer directly, I'm only getting about 300Mbps.  When connected to the router, it's the same.


FYI:

https://forums.xfinity.com/t5/Your-Home-Network/Troubleshooting-Gigabit-internet-speeds/m-p/3145413#...


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New Poster

Re: Slow Gigabit Speed

RobertWy, thanks... I had been through that article before I posted.  Good information, but still at a loss over the loss of speed.   I also did a hard reset of the CM with the recessed button on the back in the hopes that might help (it didn't).

Expert

Re: Slow Gigabit Speed

What speed do you get for the upload ?



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New Poster

Re: Slow Gigabit Speed

Ok, I think I've got the issue narrowed down.  It occured to me to try a different browser.  I'm on a mid-2012 MacBookPro running 10.14.5 with 16G of RAM. 

Firefox 68 (even starting the browser in safe mode) is topping at about 300M currently.
Safari 12.1.1 is seeing 700M currently.

I'm not sure what the issue is with FF (my default browser) but it seems to me like an update has changed something in regards to speed as I was getting close to gigbit speeds on it in the past (and no, it's not using a proxy or DNS over HTTPS).  It's also configured to use the default performance settings.

Expert

Re: Slow Gigabit Speed

For the halibut, try this speed test app. It doesn't go through any browser;

 

https://www.speedtest.net/apps/desktop



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New Poster

Re: Slow Gigabit Speed

Speedtest app: 937 down, 41.8 up, 14ms ping, 2.5 jitter, 0% loss

Expert

Re: Slow Gigabit Speed

That is exactly what is to be expected (940 'ish down due to the inherent ethernet overhead / 40 'ish up). Looks like they are giving you what you pay for.



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