Among the most frequently-asked questions in this business is: How much RAM do I need. the answer is, of course, it depends.

RAM (Random Access Memory) is temporary storage that the computer uses as workspace. If a hard drive, discussed in our last post, is like a file cabinet, RAM is like a desk–the larger the desk’s surface, the more projects you can work on at a time. The more RAM, the more workspace, the more data available to be worked on immediately.

A common perception is that adding RAM to a computer will increase its speed. This is sort of true, but only up to a point. To properly function, a computer needs a certain amount of temporary storage that it can use as working memory to store the data it is working on. The computer uses a mix of actual RAM and virtual memory for this purpose. Virtual memory is dedicated space on the hard drive that acts like RAM, hence “virtual” memory. A computer with insufficient actual RAM to carry out all its tasks will need to use virtual RAM in its place.  Which is fine, except that a hard drive, being a mechanical device, stores and retrieves data perhaps 100 times slower than RAM, which is entirely electronic. The result is a major slowdown.

If, like most people, you are still using Windows XP you probably need less RAM than you think. If all you do is surf the web, do email, occasionally listen to Itunes, and run Microsoft Office, you can get by with 512 megabytes (MB) of RAM. If you have less RAM than that, then you probably need to add a little more in any case. If you like to have lots of programs open at once, or use resource-intensive programs like Photoshop, then you probably need a gigabyte (GB) of RAM or more. Adding more memory than your system needs will not increase its performance, but not having enough will slow it down.

Note that unless you are running a “64-bit” operating system, your system will not be able to make use of more than 3 GB of RAM. Any more than that is just wasted. (A 64-bit operating system is one that moves data in 64-bit chunks, as opposed to the more common 32-bit.)  Only a couple of versions of Windows are 64-bit: Vista Ultimate and XP Professional 64-Bit. Most versions of Linux, as well as Mac OS 10, are 64-bit. Upcoming Windows 7 will also be 64-bit.