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Extremely slow download speed

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Member Since: ‎10-17-2007
Posts: 7
Message 1 of 21 (21,687 Views)

Extremely slow download speed

I am in the Northwest Indiana/Chicago area. For the past four evenings, I have had extremely slow connection speeds of around .25 Mbps. However, I got up early to run a speed test this morning. It was a lightening fast 24 Mbps. It appears as if Comcast can't handle peak traffic times. Coincidentally, the rates just went up $7 a month. Rates up and service down.

 

As I work at home and need realiable connection speeds, I am going to have to investigate alternatives.

20 REPLIES
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Member Since: ‎03-20-2012
Posts: 1
Message 2 of 21 (21,630 Views)

Re: Extremely slow download speed

I experience the same thing. I live in San Jose, CA, and a new customer.
Daytime Internet speeds are very good (20-30Mbs). At night  I cannot get the entry page at news.google.com to load!
Last night  http://speedtest.net did not load; http://2wire.com gave me 300Kbs download; that is worst than a 56KB phone modem I used 25 years ago! Just not acceptable.

Posted by
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Member Since: ‎10-17-2007
Posts: 7
Message 3 of 21 (21,621 Views)

Re: Extremely slow download speed

It took me nearly five minutes to get to this window to make a reply. But you are right - dial up would be better at this point. 

 

Everything was fine four days ago. And four days ago I complained about a rate increase. I am not a conspiracy theorist, so I don't think there is a connection, but it makes you wonder. . . . 

Posted by
Frequent Visitor

Member Since: ‎03-19-2012
Posts: 43
Message 4 of 21 (21,616 Views)

Re: Extremely slow download speed

I would recommend bypassing your router and testing the speeds again just to rule out any kind of equipment issue. It also rules out of there are any offenders on your wireless network if it is not secured, kids watching netflix etc. Bypass the router, and see how your internet works that way.

 

If your issues persist, you may be looking at signal issues or node congestion.

Posted by
Connection Expert

Member Since: ‎12-24-2003
Posts: 51,706
Message 5 of 21 (21,615 Views)

Re: Extremely slow download speed

Are your modem's signal stat figures the same (in spec) when things are bad as when they are good ?




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Posted by
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Member Since: ‎10-17-2007
Posts: 7
Message 6 of 21 (21,607 Views)

Re: Extremely slow download speed

I have a router and a Vonage box. I unplugged the line going from the Linksys router to the computer and plugged the cord (sorry, don't know technical names for them) connecting the router to the modem straight into the computer, i lost the internet connection completely. When I restored the set up to its original state, I began to receive very, very fast speeds once again. So something reset itself.

 

I just don't understand why it doesn't stay consistent. 

Posted by
Edited on
‎03-20-2012 04:52 PM

Connection Expert

Member Since: ‎12-24-2003
Posts: 51,706
Message 7 of 21 (21,605 Views)

Re: Extremely slow download speed

[ Edited ]

Please post the *Downstream Power Level*, the *Upstream Power Level*, and the *SNR* (Signal to Noise Ratio) numbers.

 

The modem needs to be properly powercycled/reset each and every time that you change the device that is being directly connected to it in order to obtain internet connectivity.




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Posted by
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Member Since: ‎03-19-2012
Posts: 43
Message 8 of 21 (21,603 Views)

Re: Extremely slow download speed

When you connect the computer directly to the modem ensure that you restart your modem, prior to attempting an internet connection.

Posted by
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Member Since: ‎10-17-2007
Posts: 7
Message 9 of 21 (21,593 Views)

Re: Extremely slow download speed

I would do this if I knew where to obtain them. 

Posted by
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Member Since: ‎03-19-2012
Posts: 43
Message 10 of 21 (21,590 Views)

Re: Extremely slow download speed

You can find this information by logging into your modems status page.

 

If you post what kind of modem you have I'll be happy to provide you with a link to the status page.

Posted by
Connection Expert

Member Since: ‎12-24-2003
Posts: 51,706
Message 11 of 21 (21,588 Views)

Re: Extremely slow download speed

Try getting them here; http://192.168.100.1

Please post the *Downstream Power Level*, the *Upstream Power Level*, and the *SNR* (Signal to Noise Ratio) numbers.




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Posted by
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Member Since: ‎10-17-2007
Posts: 7
Message 12 of 21 (21,579 Views)

Re: Extremely slow download speed

The modem is an RCA.

 

Going to that site you posted, these are the stats

 

Foward Path

Signal Acquired at 723,000 MHz

SNR: 36.6 dB

Received Signal Strength: -0.8 (fluctuating between this and 0)

Bit Error Rate: .061%

Modulation: 256 QAM

 

Return Path

Frequency: 36.4 MHz

Power Level: 43.4 dBmV

Channel ID: 1

Modulation: 64 QAM

Posted by
Frequent Visitor

Member Since: ‎03-19-2012
Posts: 43
Message 13 of 21 (21,576 Views)

Re: Extremely slow download speed

Overall your signal levels seem OK, I would recommend checking these again when the connection starts to fail. See if there is an extreme fluctuation.

Posted by
Connection Expert

Member Since: ‎12-24-2003
Posts: 51,706
Message 14 of 21 (21,572 Views)

Re: Extremely slow download speed

There are two additional signal stats which can't be read at the modem level. They can only be read from their end by them polling the CMTS (Cable Modem Termination System) at the local headend facility.

They are the 'Upstream Receive Power Level' and the 'Upstream uSNR' (upstream Signal To Noise Ratio). Both of these are as equally important in diagnosing connectivity issues as are the modem's stats.

You can call in and ask what these figures are. The Upstream Receive Power Level should fall within the range of -10dB to +10dB with 0dB being in the middle and perfect.

The Upstream SNR should be least 30dB, and the higher it is the better. You could have a noise ingress issue in the upstream channel.




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Posted by
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Member Since: ‎10-17-2007
Posts: 7
Message 15 of 21 (21,569 Views)

Re: Extremely slow download speed

Thanks. I will do that. 

 

I was getting these extremes even before I unplugged and reset the cable. I had also powered down the modem, Vonage router, and Linksys router to no avail. 

Posted by
Contributor

Member Since: ‎10-29-2011
Posts: 32
Message 16 of 21 (21,566 Views)

Re: Extremely slow download speed

Thumper i sent you a private message this morning.  the first thing i noticed is that your modem is end of life, and your modem has also had a number of resets. Modem Resets141 and that figure is just from this morning, your upstream and downstream signal levels have been fluctuating pretty badly over the last three days that i could see.  it appears that you really need a tech out to swap the modem and find out the causes for the fluctuations.

Posted by
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Member Since: ‎10-17-2007
Posts: 7
Message 17 of 21 (21,560 Views)

Re: Extremely slow download speed

I did see that, but I couldn't reply at the time. I tried later, but could no longer find your reply. So it sounds like I need a new modem? And I do this through service call?

Posted by
Contributor

Member Since: ‎10-29-2011
Posts: 32
Message 18 of 21 (21,551 Views)

Re: Extremely slow download speed

yes, a service call would handle the bad signals and the swapping out of the DCM315 modem. 

Posted by
Connection Expert

Member Since: ‎12-24-2003
Posts: 51,706
Message 19 of 21 (21,545 Views)

Re: Extremely slow download speed

You can also purchase a cable modem at retail and save the monthly fee if you like. Just be advised that if a line signal / connection quality issue exists it will still be there with a different modem.




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Posted by
Cable Expert

Member Since: ‎06-27-2009
Posts: 13,274
Message 20 of 21 (13,856 Views)
Posted by
Cable Expert

Member Since: ‎06-27-2009
Posts: 13,274
Message 21 of 21 (13,039 Views)