Dell Latitude CPx choppy video playback

I have a Dell Latitude CPx laptop, obviously an old one. I have reinstalled the operating system and everything is working fine. The only problem I'm having is when I try to watch a video on Youtube or ESPN, the playback is very choppy, to the point that it's almost impossible to see what's going on. What could be the problem? Is it just too old? Video card needs to be upgraded? Driver issue? What can I do to solve this problem? I only want to use this laptop for web browsing and watching videos on youtube. I would appreciate any help. Thanks!