amd64 Overheating on Suse 10 64 bit

Hello, I have been using suse10 an acer amd64, turion laptop. Until recently not noticed that my laptop getting over heated. I am running an Suse 10.0 64-bit version on the box. Has anyone identified/noticed if things work better on 32-bit versions or the previous versions running on 64bit box. I am quite perplexed and helpless with this. Also the fan doesn't seem to run all the time (though when plugged in or when on powersave ) ... also just goes on and off during recharge. and i never run it for a strech of more than 4 to 6 hours. All suggestions are welcome. -- Thanx ... Guru