Ubuntu 11.04 (Natty Narwhal) heating problem?

I'm currently using Ubuntu 11.04 and I've noticed that over time, my laptop has been running pretty hot every time I use Ubuntu. Also my fan runs frequently. I thought this was a problem with Unity, so I converted to Gnome 3 interface, but it still runs pretty hot. I don't experience this with Windows, so, could this be a problem with Kernal? Also, I don't run that many programs on Linux, I basically just use the web browser most of the time, but sometimes I use GIMP when I'm working.