I am using Ubuntu 12.04 LTS on a very old laptop, probably was made 7 or 8 years ago. It ran very good for a long time. However, after the recent system update YouTube videos on Chrome became extremely laggy. It is unwatchable. Also, any webpages which contains Flash are loaded very slowly. Firefox still works but not as fast as before.
I've tried the method in the link here, but it did not solve my problem http://ubuntuforums.org/showthread.php?t=1987116