Introduction – RAM, random access memory, is temporary memory used in computers. This hardware lets the computer store data in an area where it has quick access to it. RAM is memory that is dynamic and changes its contents many times during a computer session. It also loses its data when the power is turned off on the computer. This memory is available in several varieties designed to fit specific varieties of computers. A sample listing of “PNY 240-Pins 256MB PC100/PC133 SODIMM Laptop Memory” looks like a secret code to someone without computer knowledge.
Size
The 240-Pins listed in the sample is the size of the RAM chip. This is the number of connectors on the RAM slot on the motherboard. It is important to look up the size of RAM a chip before purchasing one. Pin sizes are not interchangeable on a motherboard. For example, a 240-Pin chip will not fit in a 184-Pin slot. If you cannot find the type of RAM your computer takes, remove the RAM chip and take it to the computer store with you.
Capacity
The 256MB is the capacity size of the sample RAM, which is usually in megabytes (MB) or gigabytes (GB). Gigabytes are much larger than megabytes. The size of the RAM chips is in 4, 8, 16, 32, 64, 128 and 256 multiples. Different models of computers have a maximum size of RAM that it can recognize. If too large of a RAM chip is placed in a computer, the operating system will use the chip as if it were a smaller size. Sometimes the operating system will not recognize RAM chips that are over the maximum limit.
Speed
PC100/PC133 indicates the speed of the RAM, which affect the speed of access by the computer. The most common speed is 100 MHz (megahertz) and 133 MHz. The higher the megahertz rating; the faster the access rate by the computer. Buy RAM chips that match in megahertz, which makes the computer run smoother by eliminating the need to toggle between two different speeds. The dual listing in the sample tells the buyer that they are compatible with both speeds.
Models
The SODIMM in the sample RAM stands for Small Outline Dual In-line Memory Module, which is RAM specially made for laptops. RAM chips come in different models for desktop and laptop computers. Desktop chips are long, narrow and rectangular-shaped. Laptop chips are short and square-shaped. These models of RAM memory are not interchangeable. The dimensions of the chips make accidental installation impossible.