Memory, or more specifically, Random Access Memory (RAM), is an essential part of the computer.
As the name implies, it is used to store data for quick "random" access, meaning that data in any part of the memory can be accessed at any time.
Although there are several different kinds of memory such as printer memory and video memory, this page only discusses system memory that resides on the motherboard.
Although more system memory can often be the best upgrade a computer can have, too much memory has been known to slow down computers with older processors.
At the time of this writing, 32 megabytes of memory should be enough to run most games and applications.
System memory comes in two different forms: SIMMs and DIMMs.
SIMMs are generally used on older motherboards while DIMMs can be installed in newer ones.
Some motherboards have slots for both SIMMs and DIMMs, but it is generally a bad idea to mix them because SIMMs are slower and will force the DIMMs to run at the same speed.
If you plan to purchase SIMMs, you should know that some motherboards use multiple memory sockets to function as groups or banks.
Banks can be formed from 1, 2, or 4 memory slots.
Generally, if your computer has a 386 or early 486 CPU, you probably have 4-slot banks of 30-pin modules.
Later model 486 CPUs generally use 1-socket 72-pin modules.
Pentium processors need 2-slots of 72-pin modules.
Both SIMMs and DIMMs can commonly be found in 8, 16, 32, 64, and 128 megabyte modules.
Prices for both types of RAM are generally between $1 and $1.50 per megabyte for most modules.
A Phillips screwdriver and about 30 minutes of time are required to install a memory module.
Click here for a list of links to memory manufacturers.