Dell Precision 650 - Manual (Page 122)

At start-up the BIOS identifies the components that require address space. The BIOS dynamically calculates the amount of reserved address space required.
It then subtracts the reserved address space from 4 GB to determine the amount of usable space.
l If the total installed computer memory is less than the usable space, all installed computer memory is available for use only by the operating system.
l If the total installed computer memory is equal to or greater than the usable address space, a small portion of installed memory is available for use by
the operating system.
Removing a Memory Module
1. Press down and outward on the securing clips.
2. Grasp the module and pull up.
If the module is difficult to remove, gently ease the module back and forth to remove it from the connector.
Adding a Memory Module
1. Press out the securing clip at each end of the memory module connector.
2. Align the notch on the bottom of the module with the crossbar in the connector.
3. Insert the module into the connector, ensuring that it fits into the guides at each end of the connector. Carefully press each end of the module into
place.
The memory module socket has alignment keys that allow the memory module to be installed in the socket only one way.
4. Pull up on the securing clips to lock the modules into place.
1 notch
2 memory module securing
clips (2)
3 alignment keys
1 notch
2 memory module securing
clips (2)
3 alignment keys