I have a 27", 3.06gig iMac that I bought back in January, 2010. It has worked flawlessly since I brought it home. However, lately my browser (both Mozilla and Safari) have slowed down to a crawl. Whenever I do a Google Search or click on a bookmark, it takes minutes, where it used to take seconds, to connect, if at all. All other internet programs seem to be functioning unchanged, just my browser. Any suggestions as to the cause would be appreciated. 