One set of questions that always come up relate to when computers need to be replaced, when should they be upgraded, and when can they simply be repurposed. But while the answer is pretty straight forward, the explanation generally becomes more complicated because it sometimes seems hard to justify replacing equipment that is only a few years old or “still works”. While most companies are driven by the immediate costs to replace the computer, they ignore the operational losses it could cause them over time.

Here are five limitations that usually require a working computer be retired that should be considered…

1. The cost of lost time and productivity…

Generally as time goes by most operating systems and software will have regular updates. These are often pull and apply automatically without the user’s knowledge and are added to the core code to fix bugs, modify features, and update settings. Rarely is functionality ever removed or code made smaller. These changes more commonly bloat the system over time raising the minimum requirements for older software and may even push older machines below the minimum hardware requirements for the applications and the operating system to run.

Unfortunately, while operating systems are very good at playing a shell game with resources making this loss of performance a slow unnoticeable decline, the slower performance manifests regardless and eventually will reach critical mass effecting hardware. Some things are less noticeable such as documents loading slower, saving less often, or the computer taking longer to start up or shut down. But updates can eventually bloat systems so badly that it begins to strain the hardware, exceed the capabilities of the computer all together, and then the system can fail.

2. Repurposing only works if the new requirements are lower than the old…

Repurposing computers is one of the most common ways that old and high risk computers are kept in circulation too long. Most of the time computers are not repurposed to do lighter processing, but passed from supervisors to subordinates. This practice conceals the actual age of the computer (a.k.a “How can this crash, I just got it?!”) and often passes symptoms of failing hardware and damaged software to someone else rather than removing a damaged and undiagnosed computer from circulation.

While a graphic station or a server might repurpose as a workstation for some time, repurposing computers that have been already deemed inadequate for another employee is often courting disaster. If a supervisor doesn’t have 5 minutes to wait for a document to save, can’t check email, or use the Internet than neither can the intern that inherits the computer after them. Companies make judgements about the “amount of work” or “importance” of what employees do, but system requirements are really about the minimum resources needed to function. In short, it doesn’t matter if they only check email once a day if email doesn’t work.

3. Donation and Gifting Costs Less than Disposal…

Many electronics can’t really be written off on taxes or donated at the point they aren’t functional, or else can only be donated for the cost of the metals used to make them minus the cost of processing them which is itself expensive. While a computer is still in the middle of its effective life however it can even be resold, donated, or even given to employees pretty easily to use from home and then represent a positive asset. Computers are getting cheaper and cheaper, which means that old machines can often be written off or sold on ebay for the better part of what a new computer costs.

Furthermore, it’s important to also think about the fact that the chemicals used to make monitors, computers, and devices is toxic and may bring disposal fees some areas if they have to be thrown away. Even where state law allows individuals to dump a single computer in a land fill, companies buy many of the same computers in bulk. So companies will find it much harder, more regulated, and more expensive when they have 300 similar computers to dispose of.

4. What breaks on one may indicate additional problems…

Computer manufacturers like DELL or HP pull these machines off a line and today it’s common that the flaws specific to a particular model from a particular line are common to all the computers in the lot. When a company buys in bulk they buy a group of machines that will share similar problems and failures. If the drive fails on one, it’s probably going to fail on another.

Parts in a computer are also not autonomous. A failed part may put strain and surges on other components for a long time before they ultimately fail. Adding RAM, replacing a drive, or adding a DVD drive to extend the usability of a computer is usually a good safe method to upgrade. But doing it as parts fail is questionable when the cost to do so begins to approach that of getting a new computer.

5. Expensive hardware does not usually extend the life of the computer…

Generally the best factor of when a computer needs to be replaced is when it was purchased and not what it cost. A lot of hardware like video cards, high end processors, and fast drives do not actually increase the life of the computer at all; they only give it better performance early on. Fast electronics cost more, but that is because they tend to run hotter and need additional hardware to run. Like buying a formula one race car does not mean the car will run longer with less maintenance than a sedan. Having a unique high end configuration may actually be a liability, especially if the computer was used for more intensive tasks than a standard computer.

So what is the Actual Useful Life of a Computer?

It’s hard to be told most Netbooks, Mini’s, and tablets are only going to be viable assets for one to three years, that a tower, desktop, or workstation might have to be replaced after three to four years, or that even high end graphic stations and servers may only last five. It’s equally hard to explain that no matter how much is spent on a machine that the cost is often only buying better performance, no longer effective use. But as a general rule companies should avoid upgrading or repurposing computers or electronics where the warranty is fully expired or the value to do so exceeds about one third of the equipment’s current value. This happens pretty quickly, as most low to mid-range computers now run $200-$600 while parts can run just shy of $100. But it’s important to remember that a computer that gives one user problems is potentially going to be problematic for anyone that inherits it, and without a warranty to cover parts, repurposing PC’s are often a risk compared to buying new.