How to Choose a Computer RAM

Computer RAM (Random Access Memory) is one of the most crucial components of a computer. Its main function is to provide a temporary space for data to be stored.

When a computer first starts up, the system loads information from the storage drive into the RAM. At any point of time when the system need any information, it will access the RAM to retrieve the data it needs. Since the computer RAM processes data faster than any other storage media, the retrieval process is shorter, work gets done faster and hence the computer performs better.

All RAM are volatile, which means it cannot be used to stored permanent data. Once the power is off, all the data stored in it are lost.

Tip: If you are faced with a choice between a faster processor and a 2GB memory RAM…take the RAM.

Things to look out for when choosing a computer RAM

Memory Size

Bigger memory size means there is more space to hold the data, which of course means the system can access to more data faster. A computer with 128MB RAM upgraded to 256MB RAM will show a significant improvement in the system performance. A typical gaming computer requires at least 512MB of RAM to ensure smooth gameplay.

Types of computer RAM


SDRAM is the RAM of the past and has already been phased out. SDRAM is normally used in Pentium II or Pentium III system where the processing speed is much lower. It can only process data once per clock cycle. It is usually classified as PC133*, PC100* or PC66*. *The number represents the clock speed (in MHz).

*The higher the number, the faster the RAM can process the data.


DDR RAM can process data twice per clock cycle (which gives its name double data). Thus, for the same memory capacity, it is actually processing two times faster than SDRAM.

The speed of the RAM can be classified as DDR200/PC1600, DDR266/PC2100, DDR333/PC2700 or DDR400/PC3200.
The first number denotes the maximum clock speed that the memory supports while the second number indicates the maximum transfer rate of the memory. The higher the number, the faster is the RAM. The fastest DDR RAM is DDR400


The latest addition to the DDR RAM family is the DDR2 RAM. This version of RAM has 240 pins (compared to DDR RAM 184 pins) and it has a processing speed as high as 800MHz (DDR2 800/PC6400).

DDR2 RAM is not backward compatible with DDR RAM. If you are thinking of getting a DDR2 RAM, you need to have a motherboard that supports DDR2 RAM in order to use it.

Dual Channel

Many DDR and all DDR2 desktops and motherboards have a built-in feature called dual channel that allows you to utilize the bandwidth of two modules at the same time. For these systems, you need to install modules in pairs for maximum performance, so if you want to add 512MB of memory, it will be better to buy two 256MB modules, as opposed to one 512MB one.

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