Your computer used to be fast. Now opening a browser tab takes four seconds and switching applications feels like wading through concrete. Before spending money on a new machine or a “tune-up” service that charges $100 to run a free scan, work through this list. Most slow computers can be significantly improved with free software changes and no technical expertise required.
Diagnose Before You Fix
Open your Task Manager (Windows: Ctrl+Shift+Esc, Mac: Activity Monitor in Utilities). Sort by CPU usage and then memory usage. You’re looking for processes consuming an outsized share of resources. If one application is consuming 80% of your CPU, that’s your culprit — not the computer’s overall health. If nothing stands out, the cause is likely more systemic.
10 Fixes in Order of Impact
Fix 1: Restart (Actually Restart)
Sleep mode accumulates memory leaks, pending updates, and background process buildup. A full shutdown-and-restart clears RAM, applies pending updates, and resets background processes. If you haven’t fully restarted in over a week, do this first. It solves a surprisingly high percentage of “my computer is suddenly slow” issues.
Fix 2: Remove Startup Programs
Every program that launches at startup consumes RAM and CPU before you’ve opened a single tab. Windows: Task Manager → Startup tab → disable everything you don’t need launching immediately. Mac: System Settings → General → Login Items. Common offenders: Spotify, Discord, OneDrive, Teams, iTunes, Dropbox, and manufacturer bloatware. Disabling them doesn’t delete them — they still work when you launch them manually.
Fix 3: Free Up Storage (Below 10% = Slow)
Operating systems use free disk space for virtual memory and temporary files. When drives are more than 90% full, performance degrades measurably. Run Windows Disk Cleanup or Mac’s built-in Storage Management (Apple menu → About → Storage). Empty your Downloads folder. Remove applications you haven’t used in a year. Aim for at least 15% free space.
Fix 4: Check for Malware
Cryptomining malware and adware are common causes of mysterious slowdowns. Run a free scan with Malwarebytes (Windows or Mac) — it’s reputable, doesn’t require purchase for basic scanning, and regularly catches things that Windows Defender misses. If it finds anything, remove it and rescan.
Fix 5: Reduce Browser Extensions
Each browser extension runs JavaScript continuously. Twelve extensions adds measurable overhead. Go through your extensions list and remove any you haven’t deliberately used in the past month. On Chrome: three dots → Extensions. Keep an ad blocker (uBlock Origin), remove the rest that you installed years ago and forgot about.
Fix 6: Update Your Drivers (Windows)
Outdated graphics or chipset drivers cause sluggish display rendering and application performance. On Windows: Device Manager → right-click Display adapters → Update driver. Or visit your GPU manufacturer’s website (Nvidia, AMD, Intel) directly for the latest drivers.
Fix 7: Adjust Power Settings
Windows laptops on “Power saver” mode throttle CPU performance significantly. Go to Control Panel → Power Options and switch to “Balanced” or “High Performance.” This alone can restore significant speed on laptops that have been power-managed for battery life.
Fix 8: Increase Virtual Memory (Windows)
If you have less than 8GB of RAM, increasing virtual memory paging file size can compensate. Search “Adjust the appearance and performance of Windows” → Advanced → Virtual Memory → Change. Set it to 1.5× your RAM size. This doesn’t replace RAM but reduces the frequency of performance-degrading memory shortages.
Fix 9: Defragment HDD (Not SSD)
If your computer has a traditional spinning hard drive (not an SSD — check in Device Manager → Disk drives), fragmentation increases over time as files are written non-contiguously. Windows: search “Defragment” and run the built-in tool. Do NOT defragment SSDs — it reduces their lifespan without benefit.
Fix 10: Add RAM or Upgrade to SSD
If software fixes don’t move the needle and your computer is over 4 years old: 8GB RAM is now the practical minimum for comfortable web browsing + productivity use. Upgrading from HDD to SSD is the single highest-impact hardware change you can make — computers that take 2 minutes to boot typically take under 20 seconds after the swap. Both are relatively inexpensive upgrades that can extend a computer’s useful life by 3–5 years.
Sources: Microsoft Support Documentation. | Apple Support HT201541. | Malwarebytes Technical Blog (2023). Common causes of PC slowdown.