A slow computer is one of the most common problems people bring to our workshop in Oleiros. The good news is that, in most cases, the fix is simple and affordable. Here are the most common causes and what you can do about them.

Why is your computer slow?

1. An old mechanical hard drive (HDD)

If your computer is over 5 years old and still uses a mechanical hard drive (HDD), this is almost certainly the main cause of the slowdown. HDDs are far slower than modern SSDs: Windows can take 3-8 minutes to boot on a worn HDD, versus 10-15 seconds on an SSD.

Fix: Replacing the hard drive with an SSD is the single most noticeable performance upgrade you can make on an older computer. It's inexpensive and the improvement is immediate.

2. Not enough RAM

If your computer has 4 GB of RAM or less, Windows 10 and 11 will struggle, especially with several browser tabs open at once. With 8 GB the experience improves noticeably; with 16 GB you won't notice slowdowns in everyday use.

3. Too many startup programs

Many applications add themselves to Windows startup on their own. Updaters, trial antivirus software, manufacturer apps — each one steals a few seconds. In Task Manager (Ctrl+Shift+Esc → Startup tab) you can disable the ones you don't need.

4. Viruses or malware

Some malware runs in the background consuming CPU and RAM, slowing the whole system down. If your fan is running loudly and the computer feels hot while doing nothing, that's a warning sign. We remove viruses without data loss.

5. Dust build-up inside the case

Dust acts as a thermal insulator. When the processor can't dissipate heat properly, it throttles itself down to avoid overheating. Cleaning the inside of the computer can make a 20-30°C difference to processor temperature.

6. Outdated or corrupted Windows

Windows with pending updates or corrupted system files can also cause slowness. Running sfc /scannow as administrator repairs damaged system files.

When should you call a technician?

If your computer is still slow after checking the points above, it's time to bring it in. We run a free diagnosis and tell you exactly what's wrong and how much it costs to fix, with no obligation.

Is it worth fixing an old computer?

In most cases, yes. Switching from HDD to SSD plus a dust clean can give an older computer another 5-7 years of useful life, for a fraction of the cost of a new one. We're happy to advise, no obligation.