MacOSG demonstrates how to install memory in a 2009 Mac Pro. When performing this upgrade, be sure to take precautions for static by discharging static electricity before beginning. Shut down, unplug and place the Mac Pro on a static-free surface. To access the memory, you need to open the side access door by lifting the latch located on the rear of the Mac until it locks in the open position. You can then the door forward and then remove from the body. The memory is attached to the processor tray, located in the bottom area. To remove the tray, release the latches then pull it straight forward out of the machine. On the quad-core model, there are four numbered memory slots in the front right area of the tray. To take out the existing memory, push outward on each side of the memory module and eject it. Be sure when putting in the new memory to be sure to align the off-centered pin with the off-centered nodule in the module. Push each module firmly into place. The latches will snap shut when it is done correctly. For the eight-core model, the modules are located in the front-right and rear-left area of the tray. Put the processor tray back into the Mac Pro and make sure that it is fully seated. Before closing the door, power up the Mac Pro and connect the keyboard and mouse to it. If done incorrectly, a dialogue box will appear telling you how it is installed and how it should be installed. If that happens, you will need to shut the computer down and reinstall according to the information in the box, matching the order that it should be in. If installed correctly, a box will indicate how much memory your computer has. You have then successfully completed the upgrade and can replace the door.