Ensure that you don't have any extensions running that can cause the slowdown. Visit chrome://extensions in your browser to see what is loaded and disable those you aren't using. You may also be viewing some pages that are taking up lots of memory. Visit about:memory to see what pages are taking up the most memory. Lastly, you might try running Chrome in incognito mode, which disables all extensions and see if it helps. From http://googlesystem.blogspot.com/2010/02/google-chrome-safe-mode.html:
If you want to create a shortcut that opens Chrome in incognito mode, duplicate an existing Chrome shortcut, right-click on the shortcut, select "Properties" and append this flag to the target value:
--incognito(don't forget to add a space to separate the flag).