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Help with Gig speeds please

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New Poster

Re: Help with Gig speeds please FIXED

**Update FIXED**

 

Bought a new router and confirmed the speeds on Xbox. Computer was still showing the same 2-4Mbps - found online to update Ethernet drivers. Uninstalled and reinstalled. Fixed.

 

Ended up being drivers and equipment combo.

Thank you everyone who replied!

Expert

Re: Help with Gig speeds please


@Ronny_Cordova wrote:

Huh? His return would be around 42 with a 4-way behind it. 

Think of this way...

If you have 40 dBmV at the modem and you stick a 2-way in there, the modem will report 43.5 dBmV upstream, right? 

 

So now you have 43.5 dBmV reported at the modem. Then the return path gets knocked down -3.5 dB due to the attenuation of the splitter. So 43.5 - 3.5 = 40 dBmV... which is exactly what you started with w/o the attenuation.  

 

Oh and in my division, we were taught to not do the splitter thing to attenuate, since each of the ports is a potential failure point, particularly if ppl use those 75-ohm terminators. That would fail a QC review - but that might not be universal, just my experience. 


I am not a Comcast employee, just a moderator. Pls observe Wheaton's Law.
Valued Contributor

Re: Help with Gig speeds please

Huh? His return would be around 42 with a 4-way behind it.  The whole point is to force the modem to broadcast hotter to stay off the noise floor.  Sure, they could throw a 6 pad on the tap but you would still need a cable sim to knock the high end down and now you are at two pads to go bad.  Terminated splitters are commonly used to knock down hot levels when you are only running one or two devices.  

Expert

Re: Help with Gig speeds please

@dUGNW

I suspect you have a client-side issue, but just to make sure it isn't related to signals or provisioning...

 

I've asked a Comcast employee to take a look at your account. You should expect a reply in this thread. 


I am not a Comcast employee, just a moderator. Pls observe Wheaton's Law.
Expert

Re: Help with Gig speeds please


@Ronny_Cordova wrote:

.... raise your return up into the 40s where it should be.  


Nah, that won't really work. You can't attenuate the return path, the receive level will be exactly the same as it is now. It will look better at the modem though, but it won't actually be any better. Also, an attenuator/pad is the right device to knock down a hot signal, a splitter isn't ideal. 

 

 


I am not a Comcast employee, just a moderator. Pls observe Wheaton's Law.
Valued Contributor

Re: Help with Gig speeds please

As far as the levels go all that would need to be done is someone installing a 4-way splitter with 3 of the legs terminated and a jumper going into your modem.  Depending on how your wiring is they could even just stick one in the house box outside where the main line comes to the building. It will lower your signal 7dB and raise your return up into the 40s where it should be. 

 

 Running at 9dB won't impact the service to the extent you are seeing though, it just isn't ideal.  It might be worth your while though to have them check everything out, you never know, sometimes there could be a hidden issue that we aren't seeing from just the modem diag.  

New Poster

Re: Help with Gig speeds please


@dUGNW wrote:

@dUGNW wrote:

@jweaver0312 wrote:

Try calling Comcast and obtain the following values:

 

Upstream Signal to Noise Ratio (uSNR): Should be at least 31dB

Upstream Receive Power: Should be between -2dBmV and +2dBmV with 0 perfect in the middle

In Channel Frequency Response: No higher than +2dBmV

 

They can also see a history plot of the modem to see if its been in the green or not.


I will call them later this afternoon, thank you. I will report back after


Here are the values I received

Upstream Signal Quality (SNR)  :  38.1 dB
Receive Power Level (downstream)  :   9 dBmV
Power Level (upstream) (Dbmv)  :  37.3 dBmV

Downstream Signal Quality (SNR)  :  40.7 dB


I am not entirely sure they looked up the right value, but he replied back with this also...

Channel Frequency Response: 36.7 dBmV

New Poster

Re: Help with Gig speeds please


@Ronny_Cordova wrote:

I'd really get those levels down about 9-10dB to get the modem into spec but as previously said I doubt that is the cause of the problem.  What kind of device are you using to test with?  Multiple devices or just one?  I'd lean towards a driver or hardware issue judging by the speeds you get directly wired.


I need them to send someone out to adjust those, correct?

 

I am using my PC to test the connection found here: https://www.newegg.com/Product/Product.aspx?Item=N82E16883227593

My Xbox One is also showing similiar speeds with Ethernet (different Cat 7 cable)

New Poster

Re: Help with Gig speeds please


@Ronny_Cordova wrote:

A terminated 4-way would put your levels exactly where they need to be.


Can you explain further please?

Valued Contributor

Re: Help with Gig speeds please

A terminated 4-way would put your levels exactly where they need to be.

New Poster

Re: Help with Gig speeds please


@dUGNW wrote:

@jweaver0312 wrote:

Try calling Comcast and obtain the following values:

 

Upstream Signal to Noise Ratio (uSNR): Should be at least 31dB

Upstream Receive Power: Should be between -2dBmV and +2dBmV with 0 perfect in the middle

In Channel Frequency Response: No higher than +2dBmV

 

They can also see a history plot of the modem to see if its been in the green or not.


I will call them later this afternoon, thank you. I will report back after


Here are the values I received

Upstream Signal Quality (SNR)  :  38.1 dB
Receive Power Level (downstream)  :   9 dBmV
Power Level (upstream) (Dbmv)  :  37.3 dBmV

Downstream Signal Quality (SNR)  :  40.7 dB

Valued Contributor

Re: Help with Gig speeds please

I'd really get those levels down about 9-10dB to get the modem into spec but as previously said I doubt that is the cause of the problem.  What kind of device are you using to test with?  Multiple devices or just one?  I'd lean towards a driver or hardware issue judging by the speeds you get directly wired.

New Poster

Re: Help with Gig speeds please


@Nerdburg wrote:

@dUGNW,

I'd suspect your router. Connect your computer directly to the modem vie ethernet (you'll have to power cycle the modem) and test your speeds again. 


As far as the router goes, I am using the ASUS TM-1900 which is virtually identical to the ASUS RT-AC68U. From what I can gather online, this unit should be able to reach the Gig speeds. What do you think?

New Poster

Re: Help with Gig speeds please


@jweaver0312 wrote:

Try calling Comcast and obtain the following values:

 

Upstream Signal to Noise Ratio (uSNR): Should be at least 31dB

Upstream Receive Power: Should be between -2dBmV and +2dBmV with 0 perfect in the middle

In Channel Frequency Response: No higher than +2dBmV

 

They can also see a history plot of the modem to see if its been in the green or not.


I will call them later this afternoon, thank you. I will report back after

New Poster

Re: Help with Gig speeds please


@Nerdburg wrote:

@dUGNW,

I'd suspect your router. Connect your computer directly to the modem vie ethernet (you'll have to power cycle the modem) and test your speeds again. 


That is the odd part. I power cycle the modem and plug directly in and receive only 3-4 download with a steady 35-40 upload. If I use the Comcast speedtest website it goes to about 8-10

Thoughts?

Expert

Re: Help with Gig speeds please

@dUGNW,

I'd suspect your router. Connect your computer directly to the modem vie ethernet (you'll have to power cycle the modem) and test your speeds again. 


I am not a Comcast employee, just a moderator. Pls observe Wheaton's Law.
Expert

Re: Help with Gig speeds please

Try calling Comcast and obtain the following values:

 

Upstream Signal to Noise Ratio (uSNR): Should be at least 31dB

Upstream Receive Power: Should be between -2dBmV and +2dBmV with 0 perfect in the middle

In Channel Frequency Response: No higher than +2dBmV

 

They can also see a history plot of the modem to see if its been in the green or not.

New Poster

Re: Help with Gig speeds please

To add, I have factory reset the modem and router at least twice each.

New Poster

Re: Help with Gig speeds please

Here are the stats when directly plugged into the modem, Cat 7 cable by the way. Just did a speed test. 2.91 down and 36.45 upload

 

<tabindex=-1>Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 663000000 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
Channel Lock Status Modulation Channel ID Frequency Power SNR / MER Unerrored Codewords Correctable Codewords Uncorrectable Codewords
1 Locked QAM256 29 663000000 Hz 8.9 dBmV 39.9 dB 23257761 0 0
2 Locked QAM256 1 483000000 Hz 8.7 dBmV 40.6 dB 21814195 0 0
3 Locked QAM256 2 489000000 Hz 9.0 dBmV 40.6 dB 21823439 0 0
4 Locked QAM256 3 495000000 Hz 8.8 dBmV 40.5 dB 21832855 0 0
5 Locked QAM256 4 507000000 Hz 9.0 dBmV 40.5 dB 21841855 0 0
6 Locked QAM256 5 513000000 Hz 9.2 dBmV 40.6 dB 21850891 0 0
7 Locked QAM256 6 519000000 Hz 9.1 dBmV 40.5 dB 21860155 0 0
8 Locked QAM256 7 525000000 Hz 9.2 dBmV 40.5 dB 21869562 0 0
9 Locked QAM256 8 531000000 Hz 9.1 dBmV 40.6 dB 21878627 0 0
10 Locked QAM256 9 543000000 Hz 8.9 dBmV 40.6 dB 21887834 0 0
11 Locked QAM256 10 549000000 Hz 9.0 dBmV 40.5 dB 21897832 0 0
12 Locked QAM256 11 555000000 Hz 8.9 dBmV 40.4 dB 21906907 0 0
13 Locked QAM256 12 561000000 Hz 9.0 dBmV 40.5 dB 21916623 0 0
14 Locked QAM256 13 567000000 Hz 8.8 dBmV 40.4 dB 21925788 0 0
15 Locked QAM256 14 573000000 Hz 8.6 dBmV 40.4 dB 21934970 0 0
16 Locked QAM256 15 579000000 Hz 8.5 dBmV 40.3 dB 21944925 0 0
17 Locked QAM256 16 585000000 Hz 8.5 dBmV 40.4 dB 21953693 0 0
18 Locked QAM256 17 591000000 Hz 8.5 dBmV 40.3 dB 21963325 0 0
19 Locked QAM256 18 597000000 Hz 8.6 dBmV 40.2 dB 21972389 0 0
20 Locked QAM256 19 603000000 Hz 8.6 dBmV 40.3 dB 21981947 0 0
21 Locked QAM256 20 609000000 Hz 8.3 dBmV 40.3 dB 21991638 0 0
22 Locked QAM256 21 615000000 Hz 8.4 dBmV 40.2 dB 22000734 0 0
23 Locked QAM256 22 621000000 Hz 8.4 dBmV 40.0 dB 22010222 0 0
24 Locked QAM256 23 627000000 Hz 8.4 dBmV 39.9 dB 22019088 0 0
25 Locked QAM256 24 633000000 Hz 8.5 dBmV 40.1 dB 22028607 0 0
26 Locked QAM256 25 639000000 Hz 8.7 dBmV 40.0 dB 22037676 0 0
27 Locked QAM256 26 645000000 Hz 8.7 dBmV 40.0 dB 22047226 0 0
28 Locked QAM256 27 651000000 Hz 8.7 dBmV 39.8 dB 22056307 0 0
29 Locked QAM256 28 657000000 Hz 8.7 dBmV 39.8 dB 22065803 0 0
30 Locked QAM256 30 669000000 Hz 8.9 dBmV 39.9 dB 22071761 0 0
31 Locked QAM256 31 675000000 Hz 9.1 dBmV 39.6 dB 22078948 0 0
32 Not Locked Unknown 0 0 Hz 0.0 dBmV 0.0 dB 0 0 0

<tabindex=-1>Upstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power
1 Locked ATDMA 1 30100000 Hz 37.3 dBmV
2 Locked ATDMA 2 36500000 Hz 38.3 dBmV
3 Locked ATDMA 3 17300000 Hz 36.3 dBmV
4 Locked ATDMA 4 23700000 Hz 37.3 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
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 745000000 Hz 9.5 dBmV 38.8 dB 1126 ~ 2969 17942202 0 0
2 Not Locked 0 0 0 Hz 6.2 dBmV 0.0 dB 0 ~ 4095 0 0 0

<tabindex=-1>Upstream OFDMA Channels
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
New Poster

Re: Help with Gig speeds please

When I connect directly to the modem, it either errors or gives me 2-3 down with 40 up. It's odd.

The modem is brand new and this is a brand new account/connection.

Expert

Re: Help with Gig speeds please

Downstreams are a tad on the higher side but i don't think that is causing the problem. How are the speeds directly connected to the modem? What are you getting for an upload speed? If you have recently upgraded and getting the proper upload, have you tried a factory reset of the CM1000?

New Poster

Help with Gig speeds please

Hello,

 

Can you review these numbers to ensure my modem is functioning correctly. I am using the CM1000 from Netgear and receiving 200-400 speeds. Trying to find the root of the problem (next is to ask about the router)

 

<tabindex=-1>Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 663000000 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
Channel Lock Status Modulation Channel ID Frequency Power SNR / MER Unerrored Codewords Correctable Codewords Uncorrectable Codewords
1 Locked QAM256 29 663000000 Hz 8.5 dBmV 39.6 dB 185232457 3 0
2 Locked QAM256 1 483000000 Hz 8.4 dBmV 40.5 dB 183758011 0 0
3 Locked QAM256 2 489000000 Hz 8.7 dBmV 40.6 dB 183767430 0 0
4 Locked QAM256 3 495000000 Hz 8.5 dBmV 40.5 dB 183776310 0 0
5 Locked QAM256 4 507000000 Hz 8.6 dBmV 40.5 dB 183785894 0 0
6 Locked QAM256 5 513000000 Hz 8.9 dBmV 40.6 dB 183794842 0 0
7 Locked QAM256 6 519000000 Hz 8.7 dBmV 40.4 dB 183804484 0 0
8 Locked QAM256 7 525000000 Hz 8.9 dBmV 38.8 dB 183813788 0 0
9 Locked QAM256 8 531000000 Hz 8.8 dBmV 40.5 dB 183828644 0 0
10 Locked QAM256 9 543000000 Hz 8.5 dBmV 40.6 dB 183838291 0 0
11 Locked QAM256 10 549000000 Hz 8.7 dBmV 40.5 dB 183847036 0 0
12 Locked QAM256 11 555000000 Hz 8.5 dBmV 40.5 dB 183857055 0 0
13 Locked QAM256 12 561000000 Hz 8.7 dBmV 40.3 dB 183866439 0 0
14 Locked QAM256 13 567000000 Hz 8.5 dBmV 40.6 dB 183875729 0 0
15 Locked QAM256 14 573000000 Hz 8.3 dBmV 40.3 dB 183885126 0 0
16 Locked QAM256 15 579000000 Hz 8.2 dBmV 40.2 dB 183894528 0 0
17 Locked QAM256 16 585000000 Hz 8.3 dBmV 40.2 dB 183904280 0 0
18 Locked QAM256 17 591000000 Hz 8.2 dBmV 40.2 dB 183913351 0 0
19 Locked QAM256 18 597000000 Hz 8.3 dBmV 40.2 dB 183922704 0 0
20 Locked QAM256 19 603000000 Hz 8.3 dBmV 40.0 dB 183932108 0 0
21 Locked QAM256 20 609000000 Hz 8.0 dBmV 40.2 dB 183941455 0 0
22 Locked QAM256 21 615000000 Hz 8.1 dBmV 40.0 dB 183950717 1 0
23 Locked QAM256 22 621000000 Hz 8.0 dBmV 39.9 dB 183959983 1 0
24 Locked QAM256 23 627000000 Hz 8.1 dBmV 40.0 dB 183969448 0 0
25 Locked QAM256 24 633000000 Hz 8.2 dBmV 39.9 dB 183978559 1 0
26 Locked QAM256 25 639000000 Hz 8.4 dBmV 39.9 dB 183988164 0 0
27 Locked QAM256 26 645000000 Hz 8.4 dBmV 39.9 dB 183997100 0 0
28 Locked QAM256 27 651000000 Hz 8.4 dBmV 39.8 dB 184006738 0 0
29 Locked QAM256 28 657000000 Hz 8.4 dBmV 39.7 dB 184015750 1 0
30 Locked QAM256 30 669000000 Hz 8.6 dBmV 39.9 dB 184022428 1 0
31 Locked QAM256 31 675000000 Hz 8.8 dBmV 39.8 dB 184027666 0 0
32 Not Locked Unknown 0 0 Hz 0.0 dBmV 0.0 dB 0 0 0

<tabindex=-1>Upstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power
1 Locked ATDMA 1 30100000 Hz 37.8 dBmV
2 Locked ATDMA 2 36500000 Hz 38.3 dBmV
3 Locked ATDMA 3 17300000 Hz 36.8 dBmV
4 Locked ATDMA 4 23700000 Hz 37.3 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
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 745000000 Hz 9.2 dBmV 38.5 dB 1126 ~ 2969 156430651 0 0
2 Not Locked 0 0 0 Hz 5.9 dBmV 0.0 dB 0 ~ 4095 0 0 0

<tabindex=-1>Upstream OFDMA Channels
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