Firefox CPU Usage Issue on Windows Xp

[Afznotermi]

I am running Windows Xp Pro on 3 Ghz P4 512 mb ram. I installed my windows updates and a couple of days later I downloaded and installed the update to go to Firefox 3.5.5. Whenever i start my windows, it starts normally but as soon as i open a application, cpu usage goes into 100% usage with explorer.exe as 100%. When I used the browser within a few minutes of opening it, it would ramp my CPU usage to 100% and freeze, it didn't matter if I had one tab or 5 tabs open. Can any body tell me that why i'm facing Firefox cpu usage issue on Windows Xp? Does any body knows about it? Kindly help me out to resolve the above issue. Thanks.

[Jackson2]

Firefox is the best browser around right now, with a large open-source community behind it. Some sites can cause high CPU usage through extensive use of JavaScript. You can disable JavaScript selectively using the NoScript extension. Firefox maybe the best in terms of features and flexibility, but all of this comes at a price. Firefox is a resource hog. Firefox 3 has been a lot better at managing resources, yet it has high memory usage, and occasionally, CPU usage hit 100% and the system hangs. It can take up 140 MB of RAM when multiple tabs are open.

[johnson22]

There are many reasons for Firefox hanging and/or using excessive memory. Plugins and extensions, which are not part of the default Firefox install may cause this. The fan is usually an audible indicator of CPU usage issues. Poorly optimized sites which load several images and ads may cause this. These are inevitable.

[Trio]

Firefox can cause excessive CPU usage if it's set to run in compatibility mode for an older version of Windows. Mozilla Firefox requires a significant Central Processing Unit (CPU) resources during downloads, processes and even displaying a Web content. Firefox has a CPU usage issue and, consequently, can cause overheating problems in some laptops, particularly ultraportables. More specifically, try to remove those extensions which access internet to update information for each site. You need to Disable the Java plugin, by going to Tools-->Options-->Content tab--> uncheck Enable Java. Most sites do not use Java. So, you end up wasting CPU resources for a plugin(yes, it is sorta plugin) that you do not use.