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Slow download speeds but normal upload speed in Seattle

Posted by
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Message 1 of 5

For the past 4 days, I've been getting download speeds below 1Mbit on all 4 computers in my house. But my upload speeds have been perfectly fine at 3 to 4 Mbits. Since my upload speeds are normal, can that be proof that it isn't a problem with my coaxial cables and more likely a problem with Comcast's network? I mean if my cables or splitter was going bad, wouldn't it affect the upload speed too?


-It doesn't matter if I bypass my router and directly connect my ethernet cable to my computer... still slow speeds.

-I have powercycled all my equipment a dozen times this week.

-Doesn't matter what time of the day it is... still slow download speeds.

-Fresh install of Windows doesn't help so it's not the software I'm using.

-No service outages this week... it has just been so slow.

-Average ping to Google is 23ms but to comcast.net is 119ms

-Normal trace route to Google but horrible to Comcast.net (See Below)


C:\Users\Matt>tracert comcast.net

Tracing route to comcast.net []
over a maximum of 30 hops:

  1    41 ms     2 ms     2 ms
  2    12 ms    11 ms    15 ms
  3    13 ms    12 ms     8 ms  ge-1-17-ur01.federalway.wa.seattle.comcast.net []
  4    12 ms    12 ms    13 ms  te-0-8-0-2-ar01.burien.wa.seattle.comcast.net [6]
  5     *        *        *     Request timed out.
  6     *        *        *     Request timed out.
  7     *        *        *     Request timed out.
  8     *        *        *     Request timed out.
  9     *        *        *     Request timed out.
 10     *        *        *     Request timed out.
 11     *        *        *     Request timed out.
 12     *        *        *     Request timed out.
 13   110 ms   107 ms   102 ms  te-4-2-ar01.newcastle.de.bo.comcast.net [68.86.7
 14   223 ms   204 ms   203 ms  te-1-1-ar02.ndceast.pa.bo.comcast.net [68.86.228
 15   174 ms   203 ms   200 ms  ten-4-1-ur08.ndceast.pa.bo.comcast.net [68.86.13
 16   106 ms   103 ms   105 ms  vl-81-fw-evo.ndceast.pa.bo.comcast.net [68.87.42
 17   106 ms   106 ms   108 ms  www4.comcast.net []

Trace complete.




C:\Users\Matt>tracert google.com

Tracing route to google.com []
over a maximum of 30 hops:

  1     2 ms     2 ms     1 ms
  2    11 ms    17 ms    15 ms
  3    10 ms    14 ms    12 ms  ge-1-17-ur01.federalway.wa.seattle.comcast.net []
  4    12 ms    12 ms    12 ms  te-5-3-ur02.federalway.wa.seattle.comcast.net [6]
  5    15 ms    13 ms    12 ms  te-0-8-0-2-ar01.seattle.wa.seattle.comcast.net []
  6    15 ms    39 ms    28 ms  pos-0-11-0-0-cr01.seattle.wa.ibone.comcast.net []
  7    15 ms    17 ms    18 ms  pos-0-0-0-0-pe01.seattle.wa.ibone.comcast.net [6]
  8    24 ms    18 ms    13 ms
  9    17 ms    12 ms    15 ms
 10    18 ms    20 ms    19 ms
 11    29 ms    28 ms    22 ms
 12    18 ms    26 ms    21 ms
 13    25 ms    23 ms    20 ms  pz-in-f103.1e100.net []

Trace complete.




My main question is if my upload speed is fine, shouldn't the problem not lie with my cables inside and along my house? If so, how do I convince them this when I call Comcast? Thank you for your help.

Posted by
Problem Solver

Message 2 of 5

When I had this problem (intermittent slow download and fast upload) it turned out to be a problem with the modem overheating.  If you rent the modem, ask for a replacement modem.


Posted by

Message 3 of 5


What in the world!!  I am having the EXACT IDENTICAL issue that you are.  My download speeds used to be anywhere from 15Mbps-22Mbps(on the 12Mbps plan) are now only 90kbps - 150kbps down, but my upload speeds are maintaining at their normal 3300Kbps - 3.5Mbps upload speeds as they have always been.  I am really upset, and tech support always say your modem looks good over the telephone or online chat, that's just their way of trying to get you to relax and take a step back before you request a technician comes out to fix the problem.  (I'm paranoid, I don't believe in the genuine honesty of anyone anymore.) 


I'm a little suspicious that when they realized how much bandwidth speed, (not total monthly usage), was coming through my building (my neighbors aren't internet enthusiasts, they only watched cable TV when the apt building owner paid someone to rig it up for free, and my High Speed Internet with Platinum Channel tier subscription kind of ruined that for everybody back in 2004 when the technician capped the unsubscribed connections, and made me unpopular for a short time, especially with the onsite manager), maybe Comcast throttled the speed going into my street or building since I was getting such incredible speed on the basic 12Mbps Download plan, they finally got around to it last week.  Judging by the posts here I wouldn't be the only person.  If they did I was throttled to the point I can't stand using my file downloads, I download software and legal video files as RapidShare .rar archives, and now instead of seeing them download at 1000 - 2000 kbps, they barely move at 40 - 50kbps and it reminds me of the old days of AOL dial up.  No thanks.  When cleaning out my temporary files and cookies (I like to have cookies remember some of my logins and page settings, not to mention since I am not ashamed of my online activities, I like a year-long web history to find websites I forgot where I browsed, even with my extremely well organized, folder-filed and labeled, Favorites/Bookmarks, Groups, and 3rd party software URL archives.  I don't do anything on the internet I wouldn't do in front of our criminal justice system, and contrary to what they tell you, a large Browser History will not kill your internet speed, or make your computer slow if you have adequate Memory and Cache, and multi-core hyperthreading CPU, I have done it for years without any problems, period.  Even on older inferior equipment, Pentium IV early generation CPUs with RAM modules built for Windows ME, upgraded to XP Pro and pushed to the limit.  Why do you think they put continuous browser URL History there?) I restart Windows like the techs ask me to,and it doesn't fix the download speeds like they hope it will.  Sometimes that works if your modem and network card needs a reset or something I think, but not this sort of matter.  By the way this installation of Windows 7 is only a month and a half old anyway, so the junk files couldn't be that accumulated anyway, even if that were a source of contention.  I use CCleaner and Ashampoo along with others, to get rid of the real trash I don't need. 


I just got my leased modem in June or July, it shouldn't be overheating already, but with the shabby state of electronic manufacturing these days, it doesn't surprise me that much.  I mean how can anyone tell, it always ran a little warm/hot from the beginning, it never was a cool device?  http://mydeviceinfo.comcast.net/DisplayCMDevice.php?device=84 .  I asked for a technician to come out after 96+ hours of sleepless tweaking.  I wonder if he/she will have an extra modem on their truck with him/her?  I choose to cancel important medical services tomorrow for this, I don't have an internet addiction, really.  I sure don't want to drive all the way from Denver to just North of Englewood in Denver, to get another modem like I have to do every other time I need to trade equipment, I remember all the way back since the previous company had Sega Genesis for Cable, they still trade equipment in the same building for Comcast, it's a long drive for my Personal Care Provider.  I am pretty sick to travel.  At least I don't have to take the bus anymore. 

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Message 4 of 5

Same thing was happening to me-slow download speeds (0.80 Mbps down) and normal upload (4 Mbps up)  and the modem was getting really hot and overheating (it was an old Zoom 5241 cable modem). I switched the modem (got one from a friend) and reprovisioned it. Now getting 8.3 Mbps down and 4 Mbps up on Comcast Performance. Also, check comcast's modem list for your service level. Although the old modem was compatible with comcast, it wasn't recommended for the Performance level, which might have something else to do with it.


Posted by
Connection Expert

Message 5 of 5

FWIW, this thread is over a year old.

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