Upgrade your RAM for an instant increase in speed.
Loosen the three Phillips screws securing the access door to the bottom edge of your iMac.
Remove the access door from your iMac.
Use the sharp tip of a spudger to pull the black plastic RAM tabs out of the memory bay.
Pull the black plastic RAM tab away from your iMac to eject the RAM chip.
Grab the RAM chip by its edges and pull it straight out of its slot.