First you need to remove 6 screws using a T 20 screwdriver. Two are hidden in 2 stickers.

Lift the top part of the Xbox. It can be hard.

Now you need to remove 2 cords. The power cord can be tricky. Remove 1 screw using a T 10 screwdriver.

You should lift the hard drive. Remove 2 cords and remove 2 screws. After removing the disk drive, you’ve made it to the motherboard.

Now remove this cord and remove the 2 screws holding the power supply. Yup that’s the power supply.

Take out 2 remaining cords and 4 cords shown in this picture. Look at how many screws you need to remove (there's eleven, in case you're wondering).

And finally take out the big green motherboard.