I found out this little trick from someone else on another forum.
It works AWESOME on my Mac (1.3GHZ, ~1GB ram), from what i was reading it doesn’t seem like it will work on PC- worth a try though, to me i think it makes Firefox at LEAST 30% faster.
heres the text from the other post:
install the chromedit extension… restart FF
goto tools>edit user files>user.js tab
select all and paste this text over what is there… then save and restart… firefox speeds up about 80-200 % on page loading
here’s the user.js code… again this is for a decently fast mac on broadband…
its faster, but it eats up way more of your RAM (why its so much faster) - if you’re running say PS and Flash, mabe streaming music all at the same time (me all the time) its not such a great thing… but you can adjust that first line of code to change it.
I dont see any slowdown in the rest of the applications running (mail, safari, itunes, flash, dreamweaver, photoshop, text editor, shiira, and preview-and firefox).
i like it. Flash performance is noticeably better with shiira, and everything is more instant. My only gripe is how you get bookmarks that arent stored in the main bar, but advantages are much better. Its basically safari with more speed.