First of all, unlock and remove the battery.
Turn over the laptop and open it, there are five latch holding the keyboard, open it and then remove the keyboard.
Pay attention to the keyboard cable, you also need to unplug it to take out the keyboard.
Remove the four screws to remove the cover marked “A”.
The A marked screw holds the optical drive in place.
Under the service cover, you can get access to the hard drive, wireless card and RAM.
To remove the wireless card, unscrew the screw first and unplug the cable marked below, and you can take the card out.
Now remove the memory and hard drive
Unscrew all screws are marked from the bottom.
Flip the laptop to remove the two screws and unplug the two cables. Pry up and remove the top cover.
Unscrew the screws and disconnect the connectors marked below.
Now you can lift up the motherboard.
To remove the fan assembly, just disconnect the fan cable and unscrew the screws securing it.