PC Memory Usage

If you are like most PC owners running Windows, then you probably have noticed how your system's performance seems to decline the longer that you own and use your PC. This is caused by many factors, including the Windows Registry becoming increasingly bloated when you install new applications, and files becoming fragmented across your hard drive. (There are native Windows and third-party tools to help alleviate these problems.)

But the primary source of system degradation is most commonly the use of multiple programs simultaneously. These include foreground applications that you see listed in the task bar at the bottom of your Windows display, applets seen in your System Tray, and other Windows background processes that can only be seen in the detailed system information.

What Memory Is Used?

All of these programs, regardless of their uses, must be run in system memory. When you start another application, Windows has to find memory in which to run it, and first turns to the physical random access memory (RAM) installed as one or more memory sticks on your PC's motherboard.

But there is not always enough physical memory available, especially with each version of Windows itself requiring more memory. For instance, Windows XP will run in 128 megabytes (MB) of RAM, while Windows Vista needs four times that amount!

Engineers developed the solution of utilizing free space on a hard drive as if it were system memory. Such "virtual memory" does increase the total memory available, but it does require writing to and reading from the hard disk, which is immensely slower than accessing physical RAM. (This may change in the future with hard drives based upon flash memory.)

Excessive use of virtual memory naturally causes excessive disk accessing, known as "thrashing". This in turn can cause PC owners to want to thrash the computer salespeople who assured them that 128 MB would "always be enough". A more productive (though less satisfying) response is to see if a memory upgrade would be beneficial, and if it is possible for your machine.

How Much Do You Have?

The first step is to determine exactly how much RAM your PC currently has. Admittedly, any PC user who has a strong interest in their machine's components, or built it from scratch, always knows how much memory is installed — and how much more can be added, just as soon as the funds become available. But even more PC users do not have much interest in the number, or know how to figure it out if and when they do become interested.

The fastest way to determine your Windows PC's current physical memory size, is to start Windows Explorer, click the Help menu, and choose the About Windows menu item. For instance, if the dialog box informs you that the "Physical memory available to Windows" is 523,760 KB, then you know that you have 512 MB of RAM.

Another quick way to check, assuming that you have Microsoft Office, is to click the Help menu, choose About Microsoft Word (for example), and click the System Info button. This is a shortcut to the System Information panel within Windows, which can be accessed without going through an Office component: Start > Settings > Control Panel > Administrative Tools > Computer Management > System Tools > System Information > System Summary. Hence the shortcut!

One advantage to this System Information panel, is that it lists not only the total physical memory, but also the available physical memory, and the total virtual memory, as well as how much of that is available.

How Much Is in Use?

These tools are fine for getting a snapshot of memory usage at that instant. But to see its use change from one moment to the next, you can use the Windows Task Manager: Press Ctrl+Alt+Del; click the Windows Task Manager button, and then the Performance tab.

This Performance dialogue box continuously displays your current CPU and memory usage, in both bar format and as streaming graphs. Underneath these panels, it shows the physical memory total and available, in kilobytes. In the bottom right-hand corner of the dialog box, it shows total memory usage to the left of a "/".

Let's use an example to illustrate memory consumption, and how it changes with the applications being run. My PC, with 512 MB of RAM, is currently running 12 applications, which all contribute to the usage at this moment of about 676 MB of total memory. (I thus know that virtual memory is being used.)

As each application is shut down (intentionally!), the streaming memory graph steps downward, eventually reaching about 340 MB, with only one application still running. Available memory increased to about 249 MB.

Could You Use More?

If you see that the typical number of applications that you run are consuming most of your available memory, then you should consider trying to increase that memory. This is even more true if you hear your system thrashing, as it writes memory contents from the RAM to the virtual memory on your hard drive, and then uses that freed up RAM for other needs.

If your PC is constantly swapping these pages of memory back and forth, it not only contributes to wear on your hard drive, but does the same to your patience and nerves, which can take an even greater beating as you find that your applications perform poorly. Given how the prices of RAM sticks have declined over the years, there is simply no reason not to increase the physical memory in your PC.

Well, with one exception: Your motherboard may not support additional RAM. Check the motherboard manual that should have accompanied your system if you purchased it complete, or the motherboard manual if you purchased it separately, or the motherboard manufacturer's website, searching by model number.

In most cases, the very first section in the manual lists the motherboard specifications, including that for main memory, including the maximum memory size, e.g., 3 GB.

If both your motherboard and wallet can support additional memory, then you can purchase it at a local computer shop and have them install it, or purchase it there or online, and install it yourself — depending upon how comfortable you feel working with your PC's innards. Regardless of your choice, you will likely be pleased with the superior performance of your PC.