For a few days ago I installed Ubuntu 11.10 dual boot with Windows 7 on my LenovoG555 laptop. My plan was to shift completely to Ubuntu, but i wanted to be sure it worked with my CPU. It froze during the install, but after a reboot it finished the installation and everything worked well.

But soon after the fan started to be very loud, and the CPU shut down - the computer felt very hot. It happend one more time later, when i tried to watch a video (1080dpi) on youtube; the video was lagging, the fan started making noise and the computer shut down.

I have installed one of the two suggested ATI/AMD proprietary FGLRX graphics driver; I could not install the ATI/AMD proprietary FGLRX(post-release update), but i think the first shut down occured before these installations. I have no problems with overheating (or watching 1080dpi videos in Windows).

I hope someone know this problem and a safe solution; i will not risk my hardware. I am new to ubuntu. My specs are: Windows 7Premium/Ubuntu11.10
Lenovo Win7PC (G555)
AMD Athlon(tm)II Dual-Core M320 2.10 GHz
RAM: 4,00 GB
32 bit

I will appreciate any help