Why Is My Computer Running Slow? 7 Fixes to Try
A slow computer is frustrating — but it rarely means you need a new one. The great majority of slowdowns come from a handful of fixable causes, most of them free to sort. Work through these before you spend a penny on hardware.
1. Too many startup programs
Apps that launch at boot quietly eat memory and CPU and never stop running. On Windows, open Task Manager → Startup and disable anything you don't need the moment you log in. On a Mac, check System Settings → General → Login Items. See our slow start-up guide for more.
2. A nearly full disk
When a drive fills past roughly 90%, performance drops sharply. Clear temporary files, empty the recycle bin, and move large photos and videos to external or cloud storage — aim to keep at least 10–15% free (here's how to free up space safely).
3. Background updates and sync
Cloud backup, operating-system updates and photo sync can quietly saturate your disk and internet connection, making everything feel sluggish. Let pending updates finish — a machine mid-update is always slow — then carry on.
4. Malware or unwanted software
Sudden slowdowns, pop-ups, browser changes or a fan that never stops can signal malware. Run a reputable scanner, and steer well clear of the "PC cleaner" tools advertised in pop-ups, which often make things worse. If you're unsure, don't guess — this is one of the most common reasons people bring a machine to us.
5. An ageing hard drive
Mechanical (spinning) hard drives are slow by modern standards and get slower as they age. Swapping to a solid-state drive (SSD) is the single biggest speed upgrade for most older machines — it's like fitting a new engine, and it's usually inexpensive.
6. Not enough RAM
If you keep many browser tabs or heavy apps open at once, you may simply be out of memory, forcing the machine to fall back on the much slower drive. Adding RAM (where the machine supports it) is a cheap, dramatic improvement.
7. An overdue restart
It sounds too simple, but machines left running or only ever slept for weeks accumulate clutter and pending updates. A full restart clears the slate — try it before anything else.
8. It's running hot
A dusty, overheating machine deliberately slows itself down to protect the chips, so persistent heat shows up as sluggishness. A clean-out can restore both temperature and speed.
Still slow? We can help
If you've tried these and your computer is still dragging, the issue may be hardware-related — and a quick diagnosis will tell you whether a low-cost upgrade or a repair makes sense. Our computer repair team gives honest answers, including when not to spend the money.