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Smc networks d3cm 1604 modem only 90 Mbps on 250 Mnps service?

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Contributor

Smc networks d3cm 1604 modem only 90 Mbps on 250 Mnps service?

As the subject reads. All 16 ds channels locked and great signal. 3/4 us channels locked and great signal. I’m wired directly into the modem. Comcast swears everything is as should be on their end. Help?
Diamond Problem Solver

Re: Smc networks d3cm 1604 modem only 90 Mbps on 250 Mnps service?

What do you get for the upload speed ?

Contributor

Re: Smc networks d3cm 1604 modem only 90 Mbps on 250 Mnps service?

Regularly get 11 + Mbps on uploads tests. I’m using cat 5. The run is only 5 feet. I have new cat 6a cables on the way. I’m at a loss here. It just seems like Comcast hasn’t made the proper adjustments to my account settings. My service has always been awesome. I’ve been a customer for just over 15 years.
Diamond Problem Solver

Re: Smc networks d3cm 1604 modem only 90 Mbps on 250 Mnps service?

The upload speed is correct for the Blast 250/10 speedtier. When you only get around 90 down on the faster speed-tiers it sometimes means that the port negotiation is only 10/100 rather than a 10/100/1000 (gigabit) negotiation. Is there a router in the mix here or is this with a computer connected directly to the modem ? Is that a cat5 or a cat5e ethernet cable ? Does the computers NIC / network adapter card have a gigabit capable port ?

Expert

Re: Smc networks d3cm 1604 modem only 90 Mbps on 250 Mnps service?

I don't see your modem on the list of Comcast approved devices - how long have you had it, and is this a rental, or do you own it? 


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Contributor

Re: Smc networks d3cm 1604 modem only 90 Mbps on 250 Mnps service?

I appreciate all the help!!! The only reason I purchased it, was knowing it was on the approved list. It was on this list, at one time for sure. I purchased it about 3 years ago... I think. I have tested with with 2 laptops and 2 desktops. All plugged straight into the modem. My personal pc’s motherboard is a MSI z87m. It has 1 port 10/100/1000. I’m using cat 5. If anything on my end, I feel this could be the problem... thoughts?
Diamond Problem Solver

Re: Smc networks d3cm 1604 modem only 90 Mbps on 250 Mnps service?

Try the cat6 cable when it comes. Sometimes cat5 doesn't play nice with certain devices ports.

Contributor

Re: Smc networks d3cm 1604 modem only 90 Mbps on 250 Mnps service?

Think that could be the culprit?
Diamond Problem Solver

Re: Smc networks d3cm 1604 modem only 90 Mbps on 250 Mnps service?

As I stated, "sometimes".

Silver Problem Solver

Re: Smc networks d3cm 1604 modem only 90 Mbps on 250 Mnps service?

If using windows what does it say in the Network and Sharing screen when you click on ethernet for the link speed? You could try changing the properties from auto negotiation to 1 Gb, just a thought...

Contributor

Re: Smc networks d3cm 1604 modem only 90 Mbps on 250 Mnps service?

Just tried it. Same results
Expert

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?


@strat0 wrote:
I appreciate all the help!!! The only reason I purchased it, was knowing it was on the approved list. It was on this list, at one time for sure. I purchased it about 3 years ago... I think. I have tested with with 2 laptops and 2 desktops. All plugged straight into the modem. My personal pc’s motherboard is a MSI z87m. It has 1 port 10/100/1000. I’m using cat 5. If anything on my end, I feel this could be the problem... thoughts?

It could have been on the approved list at one point, but I don't see it on the legacy site either, and that even includes ancient DOCSIS 2.0 modems. This product page on Amazon not only doesn't show Comcast as an approved ISP, but reviews show inconsistent, mixed results with Comcast. If it's not on the supported list, it's going to be hit and miss as you may not get a proper modem configuration file, for one. 

 

If the new CAT 6 cable doesn't solve the problem, you may be better off investing in a new modem. But hopefully, the cheaper fix wins out. Cat LOL

 

 

 


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Unless so specifically stated, my opinions written herein are my own and do not necessarily reflect the views of Comcast, its official employees or affiliates.


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Contributor

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?

Hmmmm thinking back, I Purchased this modem within a year after it was brought out into production. If it’s not fixed with my new cables do you have any personal recommendations on a modem?
Expert

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?

That's a long time for a modem to be around, time to put that old racehorse out to pasture Cat LOL

 

There's a lot of good modems out there (and sadly some pretty awful ones), but for your speed tier, I would absolutely go with an ARRIS SB6183, : Comcast supported, rock solid, dependable, plus a two year warranty. 


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Silver Problem Solver

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?

@darkangelic.

You're on the wrong track there, the device is still very much approved and on the list, good for Extreme 300.

It's a D3 16x4 modem.

https://mydeviceinfo.xfinity.com/device/smcnetworks-d3cm1604-426

Expert

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?

Strange, it didn't show up on the list when I was looking. Could be dependent on the market.

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Silver Problem Solver

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?

Similar to the 6183 and came out around the same time if I remember correctly and slightly cheaper.. Smiley Happy May not be as popular.

Diamond Problem Solver

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?


@darkangelic wrote:

If it's not on the supported list, it's going to be hit and miss as you may not get a proper modem configuration file, for one. 

FWIW, the config file seems to be correct since the upload speed is correct (why I asked). But there still could be a provisioning / database issue in the back end system that may only affect the download speed. These days, the config file doesn't directly control the end speeds at the modem like it used to. It now points the modem to different service flows on the CMTS configuration.

Contributor

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?

I just tried my new cat6 cables.... same result....  on both laptops and my desktop.  I am at a total loss... suggestions?

 

Version:1.0 StartHTML:000000184 EndHTML:000005290 StartFragment:000000672 EndFragment:000005219 StartSelection:000000679 EndSelection:000005219 SourceURL:http://192.168.100.1/ Modem Login

Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 531000000 Hz Locked
Connectivity State OK Operational
Boot State    
Configuration File OK  
Security Enabled BPI+

Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables
1   QAM256   531000000 Hz 2.6 dBmV 44.2 dB 0 0
2   QAM256   555000000 Hz 2.6 dBmV 44.1 dB 0 0
3   QAM256   561000000 Hz 2.7 dBmV 44.1 dB 0 0
4   QAM256   567000000 Hz 2.6 dBmV 44.0 dB 0 0
5   QAM256   573000000 Hz 2.7 dBmV 44.0 dB 0 0
6   QAM256   585000000 Hz 2.8 dBmV 44.1 dB 0 0
7   QAM256   591000000 Hz 2.6 dBmV 43.9 dB 0 0
8   QAM256   597000000 Hz 2.6 dBmV 43.9 dB 0 0
9   QAM256   507000000 Hz 2.7 dBmV 42.3 dB 0 0
10   QAM256   513000000 Hz 2.4 dBmV 44.3 dB 0 0
11   QAM256   519000000 Hz 2.7 dBmV 44.4 dB 0 0
12   QAM256   525000000 Hz 2.5 dBmV 44.2 dB 0 0
13   QAM256   537000000 Hz 2.7 dBmV 44.2 dB 0 0
14   QAM256   543000000 Hz 2.7 dBmV 44.1 dB 0 0
15   QAM256   549000000 Hz 2.7 dBmV 44.2 dB 0 0
16   QAM256   579000000 Hz 2.6 dBmV 43.9 dB 0 0

Total Correctables Total Uncorrectables
0 0

Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1   ATDMA   5120 Ksym/sec 36500000 Hz 43.2 dBmV
2   ATDMA   5120 Ksym/sec 30100000 Hz 43.2 dBmV
3   ATDMA   5120 Ksym/sec 23700000 Hz 43.2 dBmV
4   Unknown   0 Ksym/sec 0 Hz 0.0 dBmV

CM IP Address Duration Expires
  D: -- H: -- M: -- S: -- --- --- -- --:--:-- ----
Current System Time: Fri Apr 20 15:09:47 2018
Diamond Problem Solver

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?

Those stats are in spec. Try calling 1-800-comcast and ask a rep to *roll and re-provision* the modem. Also ask them to confirm that the provisioning and account data in their database is correct and complete and that the correct configuration / bootfile for your subscribed to speed tier is being pushed to the modem.

 

You may have to ask for a "Tier 2" rep.

Expert

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?

The only thing I can think of is a hard reset on the modem - there's a small Reset button right next to the LAN port Use a paperclip and press it for 15 seconds.

Comcast Experts are other customers who volunteer their time helping on the forum and have been recognized by the community. For more information on the Expert Program, please click here.
Unless so specifically stated, my opinions written herein are my own and do not necessarily reflect the views of Comcast, its official employees or affiliates.


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I am a regular customer volunteering my time to help other customers here in the Forums.
We ask that you post publicly so people with similar questions may benefit from the conversation.

Was your question answered? Mark the post as best answer!
Contributor

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?

I did notice that Its still running firmware v1.0 I looked for an update on smc website... couldn’t find anything
Diamond Problem Solver

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?


@strat0 wrote:
I did notice that Its still running firmware v1.0 I looked for an update on smc website... couldn’t find anything

Firmware does not control the speeds.

 

Only Comcast can update a modem's firmware.

Contributor

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?

Forgive me, it was hardware v1.0 So I did a hard reset.  Same results. Looks like a call to comcast with your info/suggestions is in order. TY all for all of your helpful suggestions!!!!  

Diamond Problem Solver

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?

Good luck ! If you don't get any satisfaction from a Tier 2 phone rep, I will escalate your issue to one of the Comcast corporate employees that are available to these boards.

Contributor

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?

I spoke to Byron in Colorado. He is a tier 2/3 rep. Awesome guy! I can’t say enough good things about him. Very thorough, intelligent, and insightful. He checked over everything. Spoke to other higher tier tech, said everything is in place for me to be getting the 250 Mbps service. Feels it has to be something further down the line keeping me from getting it. Tech will be here Tuesday. Let’s hope I get a good resolution. Ty all for your help! 👍🏽
Contributor

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?

got a new modem... 6183 

on ookla 300/12

on all other speed test sites 220+/11

 

 

but on xfinity speedtest... im still the same speeds... the old 90/12

 

all tests were run thru my new modem and same old router.

 

Looks like it was my old modem... wonder why testing on Xfinity site is soooo much slower?

Expert

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?

Good to see you got a new 6183 - have you tried checking the Xfinity Speed test server under Advanced Settings to make sure it's reasonably close to you?


Comcast Experts are other customers who volunteer their time helping on the forum and have been recognized by the community. For more information on the Expert Program, please click here.
Unless so specifically stated, my opinions written herein are my own and do not necessarily reflect the views of Comcast, its official employees or affiliates.


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I am a regular customer volunteering my time to help other customers here in the Forums.
We ask that you post publicly so people with similar questions may benefit from the conversation.

Was your question answered? Mark the post as best answer!
Contributor

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?

Sure, I test Pittsburgh which is the closest and then I tested two different servers in Virginia and they’re all relatively about the same speed
Silver Problem Solver

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?


@strat0 wrote:
Sure, I test Pittsburgh which is the closest and then I tested two different servers in Virginia and they’re all relatively about the same speed

Sounds like a local issue.  I am in the Houjston area and my Xfinity speed test is almost the same whether I use my nearest location or Seattle.

Did you do both IPv4 and IPv6?  There was some difference using Seattle.

 

 

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Diamond Problem Solver

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?

<removed question>

 

Would you like this issue escalated here ?

Contributor

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?

I did speak to a tier 2/3 rep as suggested. My line tests over 220 Mbps everywhere, with the exception of the xfinity test site. Wonder why that would be? As I look out the window now, there is a gentleman replacing the line to my house, as we speak. I will keep you fine folks updated! Ty so much!
Diamond Problem Solver

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?

[Edit] Sorry. I see that you did speak to a tier 2 rep.

 

O/k good luck !

Contributor

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?

Ty! 👍🏽
Contributor

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?

Yesterdays tech replaced line from pole to the house. Now my connect is bad again.... tests everywhere are 30/12, and tv service still doesn’t have on demand working... let’s see what this mornings tech visit brings.
Contributor

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?

so... my internet connection is back to about 290/12 everywhere except comcast's own speed test site... its about 100/12.  My Tv is all fixed too.  They replaced line from pole to house on monday, then today, replaced all wires inside the house and installed a new set-top box.  All tv functions are as should be.  Pings are good for gaming, as they were before any problems, with 0 packet loss. I fully believe that no lines needed replaced, outside or inside. Just my tv box... I think it was cooked or out dated.

Heres my modems readings:

Version:1.0 StartHTML:000000184 EndHTML:000005883 StartFragment:000001304 EndFragment:000005784 StartSelection:000001331 EndSelection:000005780 SourceURL:http://192.168.100.1/Status

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

 
Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Corrected Uncorrectables
1 Locked QAM256 5 531000000 Hz 1.2 dBmV 45.2 dB 0 0
2 Locked QAM256 1 507000000 Hz 1.3 dBmV 42.9 dB 0 0
3 Locked QAM256 2 513000000 Hz 1.1 dBmV 45.2 dB 0 0
4 Locked QAM256 3 519000000 Hz 1.3 dBmV 45.3 dB 0 0
5 Locked QAM256 4 525000000 Hz 1.1 dBmV 45.0 dB 0 0
6 Locked QAM256 6 537000000 Hz 1.2 dBmV 45.1 dB 0 0
7 Locked QAM256 7 543000000 Hz 1.2 dBmV 45.1 dB 0 0
8 Locked QAM256 8 549000000 Hz 1.2 dBmV 45.1 dB 0 0
9 Locked QAM256 9 555000000 Hz 1.2 dBmV 45.0 dB 0 0
10 Locked QAM256 10 561000000 Hz 1.1 dBmV 44.9 dB 0 0
11 Locked QAM256 11 567000000 Hz 1.1 dBmV 44.9 dB 0 0
12 Locked QAM256 12 573000000 Hz 0.9 dBmV 44.7 dB 0 0
13 Locked QAM256 13 579000000 Hz 1.1 dBmV 44.9 dB 0 0
14 Locked QAM256 14 585000000 Hz 1.1 dBmV 44.9 dB 0 0
15 Locked QAM256 15 591000000 Hz 1.1 dBmV 44.8 dB 0 0
16 Locked QAM256 16 597000000 Hz 1.0 dBmV 44.7 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 41.8 dBmV
2 Locked ATDMA 2 5120 Ksym/sec 30100000 Hz 41.8 dBmV
3 Locked ATDMA 3 5120 Ksym/sec 23700000 Hz 41.8 dBmV


 

Current System Time: Tue Apr 24 15:51:52 2018

 

 

I believe things are as good as can be. I am a happy customer now. I just wonder why their own speed test page is slower for me? 

Expert

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?

Cool! Just a guess here, but maybe if you restart your router, or reset it to factory settings?

Comcast Experts are other customers who volunteer their time helping on the forum and have been recognized by the community. For more information on the Expert Program, please click here.
Unless so specifically stated, my opinions written herein are my own and do not necessarily reflect the views of Comcast, its official employees or affiliates.


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I am a regular customer volunteering my time to help other customers here in the Forums.
We ask that you post publicly so people with similar questions may benefit from the conversation.

Was your question answered? Mark the post as best answer!
Contributor

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?

Yes, I have done that. Makes no sense that ALL the other speed test sites are about the same, and Comcast’s is less than half the speed. At this point, I’m as happy as I can get. Let sleeping dogs lie.... 👍🏽😁
Diamond Problem Solver

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?

FWIW, your signals stats are stellar ! The SNR figures are among the highest I've ever seen !

Contributor

Re: SMC Networks D3CM1604 modem only 90 Mbps on 250 Mbps service?

Yes, I’m lucky. My connection here has always been rock solid and faster than advertised. I am definitely a Comcast fan.