How to Install a Memory Module


Caution: Please read our safety information before attempting any testing or repairs.

Before opening the case, unplug the PC to avoid an electrical shock hazard. Exercise caution as there are sharp edges on a PC and its components. Always wear a static electricity discharge strap and attach the lead to the metal frame of the case, when working with your PC's components to avoid damaging your PC. Note that some manufacturers will void your PC's warranty if you open the case.

This article will guide you in the installation of DIMM (Dual In-line Memory Module) memory. DIMMs have 168 pins with contacts on both sides of the module. DIMMs have two notches in the contact edge of the module to ensure proper alignment during installation. RIMM (Rambus) modules have a similar design to DIMMs and use the same steps outlined below.

Inside the PC are one or more memory slots. Most PCs have two, three or four slots. The slots are numbered from zero (slot 0, 1, 2, 3). It is the best practice to install the memory starting with the lowest numbered slot. For SDRAM, it is not necessary to have a memory module in each slot, it is not necessary for the modules to all have the same capacity nor is it necessary for them to have identical characteristics. For DDR modules, they must be installed in pairs and they must be installed in slots 0 + 2 when one pair is used and if a second pair is used, they must be installed in slots 1 + 3. Each pair must be the same size and type, ideally it should be the same brand as well.

  1. Unplug the PC and open the case.
  2. Touch your hand to the power supply and the metal frame of the case to equalize any static charge. A wrist strap provides this same safety step.
  3. Locate an empty slot or the slot of the memory to be replaced.
  4. Open the latches at each end of the slot by snapping them away from the slot in a motion parallel with the slot.
  5. If removing memory, grasp the module at the middle and pull gently straight up.
  6. Note the one or two raised ridges in the slot and align the module to fit the notch(es) over the ridge(s).
  7. Press the module down firmly until the two latches snap up to secure module in place. It may help to press on one end of the module until it is secure and then press on the other end.
  8. Double check visually that the module is completely in the slot and not partially out.
  9. Replace the case cover.

The contacts should not be touched. If they become dirty, the memory may not function properly. The contacts can be cleaned with rubbing alcohol and a soft cloth.

When pressing down on the memory, do not exert too much pressure as you may break the module or motherboard. If it doesn't snap into place, try flipping up the latches at each in so that it draws the module down into the slot. If this does not work, open the latches, remove the module and double check that the notches are aligned with the ridges in the slot.

If after installing the new memory you cannot boot the PC or Windows will not start, shut off and unplug the PC, follow the steps above to remove the new memory and then restart the PC.