Many people are under the impression that a computer’s performance deteriorates with age. I want to dispel that myth: computers are mostly solid-state technology largely unaffected by age. I’m not saying that older computers don’t run more slowly. Still, once we correct the notion that its unalterable age causes the slow-down, the problem can usually be remedied without buying a newer computer.

First, let’s understand what doesn’t cause a computer to slow down:

Computer processors are digital electronic transistor-like switches sealed in a rugged plastic package; solid-state devices either work or don’t. They may get fired if exposed to a power surge, but otherwise, they don’t slow down. Computer memory comprises similar components and works or doesn’t work just the same. A computer motherboard is nothing more than wire traces on a piece of plastic, usually with more solid-state devices plugged into it or soldered. Motherboards don’t slow down, either. Computer power supplies are exposed to some of the most extreme conditions computer experiences. That’s why they burn out more frequently than most other parts, but even if they don’t cause performance reductions, they either work or they don’t.


So, what causes a computer to slow down with age?

The biggest culprit is data storage. Imagine looking for something in a file cabinet if it was the only item in the drawer; it would be easy to find, right? If there were even just a few items in the drawer, it would still be simple to thumb through them to find the one you wanted. What if the drawer was filled?

It might take a little longer, right? That happens on a hard drive when you install an operating system, applications, and data. Whenever you download more.mp3 songs, import more.jpg photos from your camera, or type up new word processing documents, you’re stuffing more things in the file cabinet, which is your hard drive.

Unlike the processor or memory, the hard drive is usually not a solid-state device; it has moving parts. Consequently, the time it takes to read or write hard drive data is 1,000 times slower than solid-state devices like RAM or a USB thumb drive. Couple that with the fact that you keep adding more and more stuff to it, and you can begin to understand the problem.

In reality, it’s even worse than you imagine. When you save a document to the hard drive, it gets stored in a specific space in the industry. The computer tries to allocate hard drive space as efficiently as possible, so if more stuff gets written to the drive after that, it’s stored in the next available sequential area. (For the hard-core techies reading this, yes, I know this

explanation severely oversimplifies the process.) Unfortunately, that means that when you next edit that initial document, there isn’t any contiguous space on the drive for the new data to be stored, so it gets stored elsewhere, separated from the first part of the document. Later, when you try to read this document back into memory, it takes a little longer than it would for a contiguously stored record because the computer must

jump in the middle of reading it to find the rest. This is known as fragmentation. Another cause of fragmentation is when files are deleted, creating holes the computer tries to fill with subsequently saved data. Still, the holes are rarely the right size for the new files being held, so the newly saved files also get broken up into noncontiguous pieces.

I don’t think your use is the only force causing fragmentation on your drive, either. Virtual memory, pointers to recent files, various cache files, and updates/patches use and release hard drive space all the time, causing fragmentation, even if you never intentionally save another file to your computer. Fortunately,

fragmentation is relatively easy to cure. Microsoft Windows comes with a tool that does it for us – all we have to do is use it from time to time, and it rearranges the files on the disk to do its best to store them all continuously. Luckily, much of the stuff we store on our hard drives doesn’t change all that frequently. Operating system files, installed applications, and even our music and photos rarely vary in content or size, so they should be fine once they get defragmented into less dynamic areas of the hard drive.


After fragmentation, the next issue to discuss how hard drives slow down our computers is the increasing volume of stored data. If you’ve seen a phonograph turntable, you have a rough notion of how a hard drive operates, but imagine it spinning much faster. Instead of 33 or 45 revolutions per minute, hard drives operate at 5,400, 7,200, 10,000, or even 15,000 revolutions per minute. Even the slowest hard drive to spin around to the

complete opposite side of the disk may take under 1/100th of a second, but like a phonograph turntable, the rotation isn’t the only motion the drive makes; the head also moves in and out radially, and that motion is significantly slower. When a hard drive has little

data, that data is generally stored close to the center. Hence, the head only needs to traverse a tiny fraction of the radius of the disk, but as more and more data gets stored, more of the radius of the disk is used, so the portion of the radius that the head must travel gets longer, making data reads and writes slower.

Fortunately, this type of performance degradation can frequently be mitigated, too. People tend to be terrible pack rats about what they store on their computers. Hard drives become like black holes, collecting years of data that may never be used, needed, or even seen again. If the computer was faster when it was new,

before it had all this data on it, you may well be able to restore it to that level of performance if you could clean out some of this data. There are countless ways to identify and remove unneeded data from a hard drive. Windows comes with a few tools that may help: