Hi everybody. I have a white MB (early 2008). I'm going to be getting an external monitor soon with a native resolution of 1920x1200 - the highest that the MB's Intel GMA X3100 will support. I know that I can open System Preferences > Display and then click the little menubar and drag it to the other monitor to make it the primary. Here is the thing: I want to just use my 24" monitor and not use the MB's screen with it (I have an external keyboard and mouse). Should I... 1. Use the two displays as an extended desktop and then (leave the MacBook lid open) just turn the brightness on the MB all the way off so the screen is black (no back light)? or... 2. Just close the MacBook and use it in clam shell mode? I watch Hulu and YouTube a lot which causes the CPU load to increase and fans to spin up.... do I have to worry about over heating? I would be using the 24" monitor exclusively all the time and then take the MB when I go to class. Will this just ruin my MB pre-maturely? Is there a different method besides theese two? What do you suggest? Thanks.