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SB6141

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Diamond Problem Solver

Re: SB6141

Hmmm. Strange. Cloning the MAC address, thereby forcing a change of the WAN / public IP address should have nothing directly to do with speeds.
Regular Visitor

Re: SB6141

Well today I tried a factory reset  on the SB6141for the 10th time with no change to the download speed. I then bypassed WRT1900AC router again and got 100mbps. Reconnected router immediately down to 46mbps. I then cloned mac address on router and power cycled everything again and then reached 100mbps through the WRT1900AC. Its very strange. I have done all of these things numerous times with the exception of cloning the mac address in the router setup which I am told makes zero difference. For anyone else using this model of router, make sure not to use the built in speedtest if you have media prioritizing enabled. The speedtest is not accurate and will change the download bandwidth setting to an inaccurate number. I found this out as well after I had everything running at 100mbps and then dropped down to 46mbps again. BTW you will have to disconnect the coax cable to the modem and powercycle the modem to make the reset option available again. I would also advise resetting the WRT199AC to factory defaults as this will eliminate any issues with corrupt settings in the router. Thanks for the replies everyone. They are greatly appreciated.

Diamond Problem Solver

Re: SB6141


MichaelCA wrote:

 

When you log into the router's signal page, are you seeing eight bonded channels in the downstream menu?   Some people have reported seeing four or less channels on their SB6141, which would affect your download speeds.

 


F.W.I.W., a current, single, 256 QAM modulated, 6.4 MHz wide, 5.120 MSym/sec downstream cable channel supports a raw data rate of approximately 43 Mbps, and a real world throughput of approximately 38.1 Mbps. 38 x 4 = 152. Theoretically, they should be able to get 100 on an uncongested cable segment / node.

Regular Contributor

Re: SB6141


mstuart88 wrote:
Hello,
I have a retail Motorola SB6141 modem and Blast 100 service. I am unable to reach speeds higher than 46mbps. I have called numerous times asked to have modem rolled and reprovisioned. Tech came out hooked up Comcast modem which reached over 100mbps and informed me that the modem was the issue. Of course he was using a 32 channel modem. I suspect I am being throttled because I have an 8 channel modem. Anyone else have the same issue and find a solution other than replacing a properly functioning modem that is capable of reaching double the speed of the service?

We had a similar issue last year with our SB6141, seeing 60 Mbps on 100 Mbps service.  But this was through a 10/100 Mbps router, which turned out to be the bottleneck.  Connected directly to the PC, it tested out at 120 Mbps.  With an upgraded router, we retained the 120 Mbps test speed.  After today's announcement and subsequent reboot, we're seeing 180 Mbps on the speed tests.

 

When you log into the router's signal page, are you seeing eight bonded channels in the downstream menu?   Some people have reported seeing four or less channels on their SB6141, which would affect your download speeds.

 

Also, before assuming it's the modem, have you tried a 2nd PC/laptop capable of 1000 Mbps Ethernet as a test?  If you have verified your issue with multiple computers connected to the modem, your next step may be to have the modem completely reset to factory defaults, then have Comcast reinitialize the modem.  Not sure if the latter is possible or whether Comcast recommends this as a last step before replacement.

Regular Visitor

Re: SB6141

Yes that is correct. I get the same speeds as I had when I was on the 50mbps plan. The speed is right around 46/11 wired and slightly less on wireless.
Regular Contributor

Re: SB6141

Sounds like the modem has the right config file for the speed tier. 

 

You said when you hooked up the PC directly to the modem you were still getting slow speeds?  

Regular Visitor

Re: SB6141

11.37mbps
Diamond Problem Solver

Re: SB6141

OP. What are you getting for the upload speed ?

Regular Contributor

Re: SB6141

Has anything changed with the router location?  Anything plugged into the USB ports or the like? Check the anntennae to make sure they're secure.  You might have had a radio go out inside the router causing you to be downshifted to the 2.4Ghz band which could explain the speed limitation as well.

 

I would check the radio side of it using "wifi analyzer" app on your phone that you can download for free.  Check for your SSID on 2.4/5ghz and if you see it only on 2.4 then there's a chance you might want to pick up a new router.

Regular Visitor

Re: SB6141

Hi,
Thanks for replying. That speed is wired directly to modem from PC with gigabit Ethernet port. It is around 42mbps using wifi and WRT1900AC router.
Regular Contributor

Re: SB6141

I would disagree with the tech.  I had a Zoom 5363 combo CM/Rotuer and it was also a 8x4 modem as well.  I had more of an issue with the WIFI side of it with some latency but, consistent speed tests consitent with my plan.  

 

I would first have to ask if your'e connecting over wifi or Ethernet when getting the 46M number?

-- If you're on WIFI what type of router do you have?

 

Have you tried a different Ethernet cable to see if you might have a bad cable?

 

If the tech provided modem was testing out over 100M then I would say it's not a line issue or anything else.

Regular Visitor

SB6141

Hello,
I have a retail Motorola SB6141 modem and Blast 100 service. I am unable to reach speeds higher than 46mbps. I have called numerous times asked to have modem rolled and reprovisioned. Tech came out hooked up Comcast modem which reached over 100mbps and informed me that the modem was the issue. Of course he was using a 32 channel modem. I suspect I am being throttled because I have an 8 channel modem. Anyone else have the same issue and find a solution other than replacing a properly functioning modem that is capable of reaching double the speed of the service?