Page 3: Memory (RAM)
The second most important consideration in a new computer is memory. At least, it was at one time. Now a days, most computers come with ample memory. The considerations for this characteristic come down to amount, type, and speed.
Most current computers come with 4GB or more of RAM. For the ‘typical’ user, this is more than sufficient. It is possible to gauge the amount of RAM one needs by opening some commonly used programs, and noting the values under the ‘Performance’ tab of ‘Task Manager’. Typically, 2GB of RAM should suffice for day to day computing, and 4GB should be more than enough for everything the typical user will do. A special consideration is that one must have a 64-bit operating system to use more than 4GB of RAM.
Most RAM is currently of either the DDR2 or DDR3 interface. In DDR2, the RAM transfers data in chunks twice as large as DDR, and in DDR3 the chunks of data are three times as large as DDR. Typically though, the time for each data transfer (termed ‘timings’) is increased as the chunk size increases. None the less, DDR3 does offer a speed improvement over DDR2, and has recently overtaken DDR2 in offering better price per GB.
The third consideration is speed. This is typically a function of the data rate which is appended to type (e.g. DDR3-1333 has a data rate of 1333MT/s) the higher the value, typically the faster the RAM (although, again, timings tend to drop as the data rate increases).
As the older types of RAM tend to increase in price, it is generally wise to go with the current mainstream RAM – this will be the least costly, and provide the best performance. The most recent RAM technology (in this case DDR3, which is also the mainstream type) also offers the best prospects for affordable future upgrades. Lastly, each generation of RAM tends to be accompanied by a power drop, which translates into less heat and longer battery life.
Lastly, one should consider the number of ‘channels’. This basically refers to how many individual modules of memory can be written to/read from at the same time. Currently, there is single channel (one memory module can be accessed at a time), dual channel (two memory modules can be accessed at the same time), and triple channel (three memory modules can be accessed at the same time). In effect, each channel increases the speed the RAM operates at. Triple channel has not yet gained wide mainstream popularity. It is advisable to go with dual channel memory, as it offers a considerable speed improvement over single channel memory.
A good choice at the moment would be 4GB of dual channel, DDR3-1333 RAM.