Virtual Memory (Windows)

Sometimes your computer needs to use more RAM than it actually has. In order to make up the difference, it uses some space on your hard drives and "pretends" that it's just like normal system memory (RAM). This "virtual" memory is also known as your computer's paging file.

Unfortunately, your hard drives transfer data at a MUCH slower rate (on the order of 100 times slower), the practical offshoot of which is that your programs will run verrrry sloooowwwllllyy. As it turns out, Windows always uses a little virtual memory for its own mysterious purposes, but if it must resort to using VM every time you open a new program, you're experiencing a RAM shortage.

So, how can you tell when your computer is tranferring stuff into virtual memory? Check your hard drive activity light: if it starts flashing (usually accompanied by the "clicking" noise that computers make when accessing hard drives) every time you start up a program (or even boot into Windows), you're probably overusing your virtual memory. There are two causes for this:

1. You have too many programs/services/spyware instances running at the same time (see Computer Cleanout)
2. Your computer doesn't have enough RAM (see the RAM buying guide)

Frequently, the cause is a combination of these two. Users running Windows XP with 256MB or less will probably experience RAM shortage. First try cleaning out your machine -- if things are still running slowly, consider buying more RAM.

How do I change how much virtual memory my computer uses?

Well, the answer is that Windows will use as much or as little as it really feels like. However, you can set maximum and minimum values for the file, as well as change its location.

Go to Start > Control Panel > System > Advanced Tab > Settings button in the Performance box > Advanced> Tab > =Change button under Virtual Memory

From there you can change max, min, and location values.