How To Install a Memory Module

This article guides you in the installation of DIMM (Dual In-line Memory Module) memory. DIMMs have 168, 200 or 240 pins with contacts on both sides of the module. DIMMs have one or more 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.

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.

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.

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.