Hacker hacking wunderkind Bunnie Huang deconstructs an XO laptop and details his findings:
Thanks in part to the low power of the Geode CPU, the design mounts the motherboard against the LCD, unlike most laptops where the motherboard is under the keyboard. This configuration has some simplicity advantages, especially considering the flexibility required by the display unit that can be flipped 180 degrees in either direction. The heatsink for the CPU consists simply of a thin metal heat spreader, which is in close proximity to the plastic casing: no cooling holes, fins, or fans to collect dust and break (notice how the Intel Classmate PC features prominent cooling holes for its under-keyboard CPU module). It also doesn’t burn your lap up while you are using it (although the display still does get quite warm when you use it-I tucked it into my jacket once to keep me warm while running around outside in the cold).