My Macbook is running hot. I've read numerous posts on all kinds of sites, and still can't figure this out. Please help. With no applications open (except for Dashboard, which runs 2 widgets) my CPU use is at 50%, CPU temp at 153F, and my fan speed around 5800. This seems to never change, no matter what the load. I have checked my Activity Monitor and see nothing unusual there. (I've attached a screenshot) My fan is working fine as well. What gives? I did do some recent upgrades, but between the upgrades and this, there was a time of great peace - no heat, no fans whirring away! Upgrades - New 7200 rpm Harddrive (320 gb Hitachi), added a 2GB RAM module, and also made my Macbook dual boot with Ubuntu. I should note that in Ubuntu, it does not run as hot. Thanks in advance!