Safari extremely slow

Question

For about a week now a large number of sites have been extremely slow. I try reloading them, etc. which sometimes helps, but it just isn't running smoothly like it used to. I tried resetting it, emptying the cache, and nothing seems to help. I had hoped that when the new system update was installed it would fix it.
Any advice would be appreciated.
<Edited by Moderator>

Answer 1

I have tried everything too!
Maybe not!
The following usually works on both Tiger and Leopard:
(First, if yours is an Intel Mac, check that Safari is not running in Rosetta, which is enough to slow it to a crawl.)
Empty Safari's cache (from the Safari menu), then close Safari.
Go to Home/Library/Safari and delete the following files:
form values
download.plist
Then go to Home/Library/Preferences and delete
com.apple.Safari.plist
Repair permissions (in Disk Utility).
Start up Safari again, and things should have improved.
If not, MacFixit have published a very detailed (very!) article on speeding up a slow Safari, here:
http://www.macfixit.com/article.php?story=20070416000657464
Many, including me, have also followed the advice given by others here to add DNS codes to their Network Settings, with good results in terms of speed-up:
Open System Preferences/Network. Double click on your connection type, or select it in the drop-down menu. Click on TCP/IP and in the box marked 'DNS Servers' enter the following two numbers:
208.67.222.222
208.67.220.220
Click on Apply Now and close the window.
Restart Safari, and repair permissions.
If none of that worked, run the 10.5.4 combo updater again, as this contains the Safari update for Leopard.