Any time a computer component stops working, or just becomes unstable — as we all know will happen from time to time — we have to decide whether to replace it, have it repaired, or just get by as is with perhaps a temporary fix. Repair or just getting by will nearly always be the cheapest solution, at least in the short run. Replacement, however, will usually provide a good opportunity to upgrade. In fact, given the rate at which the various technologies behind computer hardware are advancing, unless you replace something a week after you buy it, you may almost be forced to upgrade.

Following are five items which, if replaced (and generally upgraded), can provide excellent benefits, from an enhanced user experience to additional compatibility, greater longevity, and stability for the whole system.

#1: Power supply

One of the most overlooked pieces of computer hardware is the power supply unit (PSU). Computer enthusiasts often brag about their blazing fast processors, top-of-the- line video cards, and gigs upon gigs of RAM, but rarely about their great PSUs.

The truth is, the power supply is the last thing we should skimp on when choosing components for our system. If a computer’s brain is its processor, its heart is the power supply. And having one that is worn out, underpowered, unstable, or just generally cheap can be a major cause of hardware failure.

Every computer’s power requirements are different, but a good minimum for a modern PC is 450 watts. Some systems, especially those with multiple high-end video cards or lots of add-on cards and peripherals may require a PSU rated at 800 watts or more. Replacing a failing or inadequate power supply can make a previously unstable system stable.

Aside from supplying enough power, that power must be supplied stably. A common cause of “unexplained” lockups and system crashes is a drop in voltage supplied to the system when under load, caused by a poorly manufactured PSU. The easiest way to find a quality PSU is to stick to the consistently top brands such as Antec, EnerMax, and PC Power & Cooling.

#2: Fans

As computers have gotten more powerful over the last decades, they have also gotten hotter. Gone are the days of a passively cooled Pentium 100; now we have fans on our massive CPU heatsinks, on our monster video cards, and on intake and outtake vents to our computer cases. All of these fans are playing important roles by keeping our computers safely cooled, and we should try to ensure that they continue doing so.

Fans are one of the few parts that when replaced will not usually be replaced with something better. But they deserve mention because:

  • As one of the few moving parts in our system, they are one of the most likely to actually break.
  • When they break, it’s likely to pass unnoticed or not cause much concern.

Also, fans are cheap and easy to replace. It generally takes about £10-£15, 15 minutes, and a screwdriver to install a new one, so there’s really no good excuse for not doing so.

#3: Surge protector / UPS

This is another item that keeps our computers safe and should not be neglected. A surge protector can be a stand-alone power strip, but one is also built into virtually every uninterruptible power supply (UPS). The surge protector guards our devices against spikes in energy that occur in our circuits at the home or office, usually due to lightning or the powering up of high-powered devices, such as hair dryers or refrigerators. Repairing a surge protector would be difficult and expensive at best; replacement is almost always the best option.

It can be tricky to know when it’s time to replace a surge protector, because the component inside that diverts excess power from surges to the ground simply wears out with repeated use. However, there is often no interruption of power or other indication that it’s done. You may still have juice but not be protected. The cheapest protectors may wear out after fewer than 10 small surges, while the better ones can last through hundreds. The safest thing to do is to get higher quality protectors but still replace them occasionally.

#4: Video card

The video card is one of the most important elements in the performance of your system and overall user experience. Even though it is also one of the priciest components, there are two good reasons to replace it should your old one bite the dust.

First, video cards are one of the components that are being improved upon seemingly every day. Just like with CPUs, a video card that’s two years old simply isn’t as fast as a current one and won’t have the newest features (such as support for DirectX 10).

Also, the video card is the number one hardware stopgap as we migrate to Vista. Manufacturers just aren’t providing new Vista-compatible drivers for lots of their old video cards. This means that many of us will have to replace our video cards whether they are broken or not, if we plan to switch to Vista.

#5: Hard drives

The computer component we all least want to fail is the hard drive. It’s easier to cope with the loss of the much more expensive processor or video card as long as we still have our precious data, so your first instinct is to try to repair it. But if you’ve been practicing good backup habits, you can actually come out of the situation better off when you replace the old drive with something bigger and faster. Generally you want to look for the largest drive you can find, Maxtor, and Seagate are good brands to look for.

Adam Brown, technical advisor