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Why is Firefox so dreaded slow compared to IE9?

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Ok, I was basically still working the adobe flash player issue, and I stumbled across some speed test info. So I decided to play Firefox 13.0.1 off against IE9. Same PC, procedure, start Firefox, run speed test, shut down Firefox, open IE9, run test again at same site, same PC, same internet connection, yada yada. This blew me away, and I tested on 2 sites, speedtest.org and speedtest.net. Oh yeah, using Charter cable internet, Charter cable modem, direct wire connection to router on this PC.

Results: IE9 - download 52.7Mbps, upload 3.6Mbps; Firefox 13.0.1 - download 1.6 Mbps, upload 2.1 Mbps !!!! Geeze, what is up with this thing???!!!! And it's repeatable, over and over and over. No wonder video via Firefox sucks! (pardon the expletive)

I'm just a simple 65 year old, I just want stuff to work, and this just seems ludicrous, almost like it can't be true, but the 2 speed test sites compare closely to each other, with both browsers under test.

In addition, video via IE9 is super, regardless of source, my Netflix "experience" via PS3 is superb, and also VUDU via my Mits, which pegs it's speedtest.

My only conclusion is there is something wrong with Firefox, at the core, and it seems to me to be with this version, I just don't remember this stuff before.

Ok, I was basically still working the adobe flash player issue, and I stumbled across some speed test info. So I decided to play Firefox 13.0.1 off against IE9. Same PC, procedure, start Firefox, run speed test, shut down Firefox, open IE9, run test again at same site, same PC, same internet connection, yada yada. This blew me away, and I tested on 2 sites, speedtest.org and speedtest.net. Oh yeah, using Charter cable internet, Charter cable modem, direct wire connection to router on this PC. Results: IE9 - download 52.7Mbps, upload 3.6Mbps; Firefox 13.0.1 - download 1.6 Mbps, upload 2.1 Mbps !!!! Geeze, what is up with this thing???!!!! And it's repeatable, over and over and over. No wonder video via Firefox sucks! (pardon the expletive) I'm just a simple 65 year old, I just want stuff to work, and this just seems ludicrous, almost like it can't be true, but the 2 speed test sites compare closely to each other, with both browsers under test. In addition, video via IE9 is super, regardless of source, my Netflix "experience" via PS3 is superb, and also VUDU via my Mits, which pegs it's speedtest. My only conclusion is there is something wrong with Firefox, at the core, and it seems to me to be with this version, I just don't remember this stuff before.

All Replies (11)

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Which security software (firewall, anti-virus) do you have?

Your security software may be blocking or restricting Firefox.

You can test that if you boot the computer in Safe mode with network support (press F8 on the boot screen).

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Pardon me for being obtuse, but since the tests were run back to back to back to back (2 full series, 1 each at each site for each browser), why in blazes would the security software be an issue? (it's Charter security suite btw, which runs off the F-secure engine I believe) Are you trying to say F-secure is saying to itself "gee, IE 9 is going to www.speedtest.org so I better let it go really fast", followed by "oh no, Firefox is going to www.speedtest.org, so I better clamp right down on it!"?? I'm not buying that for a heartbeat, but hey, I'll go through the hogwash of booting without it and rerunning the test, just for grins, stand by, it'll take a bit. Also, why not just disable the security suite? Heck of a lot easier than booting to safe mode??

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Ok, I did the boot safe mode thing, and ran the speed tests, almost parity, but IE is still the faster browser now, 64.7 Mbps in safe mode, to 47 something with Firefox. (did not try Chrome) After that I booted back to normal and disabled all the plug-ins, and then turned them on until I found the roadblock. Seems to be the Adobe flash plug-in. And that leads to another whole ball of wax.

So - if anybody cares, Firefox HAS to play with Adobe and Real Player if they want to play like a big boy in the browser world. Period. I don't care WHY the problem exists suddenly with this version of Firefox. Get it? It's this simple, works fine with IE, very fast. Works crappy with Firefox, very slow. Absolutely simple, the CUSTOMER (that's me) chooses fast, seamless operation over klunky slow operation. (I also DO NOT CARE WHO IS AT FAULT, Adobe, Mozilla, or Real Player, it DOES NOT MATTER) (Nor do I care if it can be FORCED to work better by using an old version or what ever, it needs to work in it's default state, with updated software from every provider)

After flogging this issue for a fair amount of time and finding out what I now know, I choose to use another browser. This issue is NOT SOLVED until the current version of Firefox will run the current version of Flash, at the same high speed / quality as previous versions. Period.

I am now switching over to IE 9. Bye.

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I have this problem too i clear the cache clear all the history disable all the addons did a reinstall.But still slow im on the 30/4 Charter cable plan.I usually get about 45 Mbps on IE 9 or Chrome looks like i might switch to a different Broswer unless theres a solution.

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Well, I solved the problem completely. I am back to full speed, no problems with video's, youtube, or anything else. Pretty simple. Back up your bookmarks and cookies if you want them. Remove all vestiges of Firefox from your computer, full uninstall of everything Firefox. Then install IE9. Done. Everything works, seamless, you don't have to be a computer geek to use it, it just works. The roles have reversed, Firefox once was a performance leader and IE was a resource hog, big and clunky. Now it's Firefox which is big and clunky and hard to use, IE9 appears to be lean and mean, at least it performs as such, so who cares what's under the covers. It works, Firefox don't. cheers cj

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I agree being a Charter Cable customer and Having problems with Firefox the last year.Why should i have to go through all the trouble shooting steps when IE9 and Googles Chrome have been working fine the last 2 years for me.when i did the speedtest.charter.com yesterday and today i got 3Mbps download on Firefox what a joke and on IE9 and Chrome 44 Mbps.It seems IE9 is blazing fast on Charter.Looks like im gonna switch back to IE9 too many problems with Firefox 14.0.1 .So for Charter Cable costumers i suggest using IE9 or Chrome.

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To buddha17

Which security software (firewall, anti-virus) do you have?

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Charter Security Suite, I use the same settings on IE9,Chrome,and Firefox,Had no problems IE9 and Chrome but Firefox as of lately seem u have to do this or that to make it run.For instance Adobe flash player.

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I am afraid the answer isn't saying "bye bye" to Firefox. Riddle me this...Why does Firefox work like a fine oiled machine when used with other security antivirus software? I have tested them all and the problem is something with Charter Security Suite. I currently use a well known security program offered by Charter competitors. You get at least 3 licenses per household and a lot of people use only one computer in their home. Just use one of their licenses. Bottom line? Do NOT use Charter Security Suite, EVER! It wouldn't surprise me if Charter SS is tinkering with things so people will go to a different browser. If this is so, then Charter should be held accountable for unfair business practices. I just think it's very odd that only when CSS is running only then does Firefox slow down. I have been through countless settings and the only thing that works is do NOT use CSS.

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I also never use IE

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if you are using Charter Security or F-Secure and having performance issues on sites using flash please make sure that enhanced process monitoring is disabled in advanced settings > computer > deepguard since it might interfere with adobe flash' protected mode.