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opening second tab, no address causes download speed to drop from 160 kbs to less than 5 kbs and sits there doing nothing, does not happen with IE, why is this

  • 3 การตอบกลับ
  • 5 คนมีปัญหานี้
  • 1 ครั้งที่ดู
  • ตอบกลับล่าสุดโดย cor-el

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after firefox updated from 27 to 28, when i download a file, play music, watch a video, or run a speed test, normal speed is about 160 kb/s (dsl connection 1.3 Mb/s) - just opening another blank tab (not any address) or try to open another page like google search page, download speed drops to less than 5 kb/s - downloading stops, and second page does not open, why is this happening, it does not happen with internet explorer and the version of IE i have is out of date,


history/cookies all clear automatically when close, i have disabled all add on, run malware, adware searches - show no problem, norton antivirus is up to date, i have spent hours on phone with ATT isp and connection is showing no problem - if i run a speed test it shows good, if i try to run a speed test and open second tab - speed fails and speed test will not even finish, ATT suggested I try the same thing in IE and there is no problem - so it appears to be an issue with Firefox 28

after firefox updated from 27 to 28, when i download a file, play music, watch a video, or run a speed test, normal speed is about 160 kb/s (dsl connection 1.3 Mb/s) - just opening another blank tab (not any address) or try to open another page like google search page, download speed drops to less than 5 kb/s - downloading stops, and second page does not open, why is this happening, it does not happen with internet explorer and the version of IE i have is out of date, history/cookies all clear automatically when close, i have disabled all add on, run malware, adware searches - show no problem, norton antivirus is up to date, i have spent hours on phone with ATT isp and connection is showing no problem - if i run a speed test it shows good, if i try to run a speed test and open second tab - speed fails and speed test will not even finish, ATT suggested I try the same thing in IE and there is no problem - so it appears to be an issue with Firefox 28

การตอบกลับทั้งหมด (3)

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Hi BC8088, Firefox does not control the allocated bandwidth for specific traffic types on your network. Each download request will however create another process/connection on your network that may require the available network bandwidth. Therefore, the more traffic/connections on the network, the lower overall connection speed. Please talk to your network provider for more information.

If you have any other questions, we are happy to help.

There are also some work arounds for pipelining that you can try to improve the speed: http://www.youtube.com/watch?v=KPnXFL2huZs

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Hi BC8088,
Do I understand this correctly ?

Are you saying that if you run some speedtest as the only open tab, and then with no background downloads you simply open a blank tab such as about:blank (key about:blank into the addressbar) that download speed plummets from about 160kb/s to 5kb/s

To me that would appear to be a fault. That would not even be opening a new network process.

You have a lot of addons. As a test please try in safe mode and with all plugins disabled.

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What is the CPU load when this slowdown happens?

Are you using a specific driver in Windows to mange the internet connection that might not get enough processor time to run properly?

It is also possible that other (security) isn't able to do its work and takes additional CPU time.

Boot the computer in Windows Safe Mode with network support (press F8 on the boot screen) as a test to see if that helps.


You can try to create a new profile as a test to check if your current profile is causing the problem if starting Firefox in Safe Mode didn't help.

See "Creating a profile":

If the new profile works then you can transfer files from a previously used profile to the new profile, but be cautious not to copy corrupted files to avoid carrying over the problem