Add-ons can impact your browser’s performance and drastically slow it down. Internet Explorer 8 lets you quickly identify which of your add-ons is the culprit. Within Internet Explorer, click the Tools menu and select Manager add-ons. The Manage Add-ons window appears listing all add-ons currently loaded. To determine which add-on is hindering performance, check the load time for each add-on in the list.
The load time is the average amount of time in seconds that an add-on takes to load and finish initializing. Every time Internet Explorer 8 starts or you open a new browser window, these add-ons are created and initialized. Therefore, an add-on with a high load time can cause IE to run slowly. Once you identify which add-on is causing the problem, you can disable it from the Manage Add-ons window.