Upgrades & repair

Why your old laptop is slow, and the afternoon that fixes it

It's almost never "too old." It's a hard drive, a fan full of dust, thirty programs launching at startup, or dried-out thermal paste. In order of effort, here's how to find out which and fix it.

·4 min read

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In short

  • Start with the free fixes: startup programs, disk space, browser extensions, a malware scan. Twenty minutes, often a big difference.
  • A laptop that gets loud and slow after ten minutes is overheating. Dust in the fan is the usual cause; five minutes with an air duster fixes it.
  • If it has a mechanical hard drive, nothing else will matter as much as replacing it with an SSD.
  • A laptop five years or older that's still hot after cleaning has dried-out thermal paste. Replacing it is an hour's job.

"It's just old" is the least useful diagnosis in computing. A laptop doesn't slow down because time passes. It slows down for specific reasons, most of which are fixable in an afternoon for little or no money. Work through these in order; stop when it's fast.

First: the free fixes (20 minutes)

  1. Startup programs. Open Task Manager (Ctrl+Shift+Esc) → Startup tab. Sort by "Startup impact" and disable everything you don't need running from the moment Windows starts: updaters, chat apps, printer utilities, anything you've never heard of. You can still open them when you want them. Restart.
  2. Disk space. A nearly full drive makes Windows crawl. Settings → System → Storage shows what's taking the space; turn on Storage Sense and run "Temporary files." Uninstall programs you don't use from Apps & features while you're there, especially trial antivirus suites, which are slow and redundant next to the built-in Windows Security.
  3. Browser extensions. Most people's slow laptop is a slow browser. In Chrome or Edge, open the extensions page and remove everything you don't actively use. Fewer than five is a good target.
  4. A malware scan. Windows Security → Virus & threat protection → Scan options → Full scan. Let it run while you do the next step.
  5. Windows Update. Install everything pending, restart, check again. A machine that's mid-update in the background is a slow machine.

Second: find out what drive it has (30 seconds)

Press Start, type defrag, open Defragment and Optimize Drives, and read the Media type column. If it says Hard disk drive, you've found the main reason, and no amount of tidying will fix it. Replacing it with an SSD transforms the machine; it's an evening's work and by far the most effective thing on this page. Do the cleaning below anyway, then do the SSD.

Third: dust (10 minutes)

Here's the pattern that gives it away: the laptop is fine for a few minutes, then the fan gets loud and everything slows to a crawl. That's the processor overheating and deliberately slowing itself down to survive. After three or four years, the fan and the heatsink fins behind the vent are usually packed with a felt-like mat of dust that blocks the airflow.

  1. Shut down and unplug.
  2. Find the vents: an exhaust on the side or back, an intake underneath.
  3. Blow air through them in short bursts with an electric air duster or a can of compressed air. Aim through the exhaust vent toward the intake and back again. Hold cans upright, or they spray liquid.
  4. Stop the fan spinning while you do it, if you can get a toothpick through the grille: a fan spun up by compressed air can damage its bearing.
  5. If a lot came out, go further: remove the bottom cover (search "[your model] fan cleaning" on YouTube), lift the fan, and pull the dust mat off the heatsink fins by hand. This is the fix that actually works on a badly clogged machine.

For the dust

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Fourth: check the temperatures

Install HWiNFO or Core Temp, both free, and watch the processor temperature while you play a YouTube video. Under 70°C is fine. Over 90°C with the fan roaring, after you've cleaned it, means the thermal paste has dried out.

Fifth: thermal paste (an hour, laptops five years or older)

Between the processor and its heatsink is a thin layer of paste that conducts heat. Factory paste dries to chalk after several years, and a laptop with chalk in that gap will overheat and throttle no matter how clean the fan is. Replacing it is the one "advanced" job on this page, and it's less scary than it sounds.

  1. Watch a teardown video for your exact model so you know how many screws stand between you and the heatsink. On many business laptops it's the bottom cover plus four spring screws. On some consumer laptops it's the whole machine; if so, a repair shop will do this for the price of an hour's labor.
  2. Remove the heatsink, loosening the screws in the numbered order marked on it, a little at a time.
  3. Clean both surfaces with 99% isopropyl alcohol on a lint-free cloth until the metal shines.
  4. Apply a pea-sized dot of new paste to the center of the processor. Don't spread it; the heatsink pressure does that.
  5. Refit the heatsink, tightening in the same numbered order, and put it back together.

For the repaste

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Sixth: memory

If Task Manager → Performance → Memory shows 4GB and it's regularly nearly full, the machine is swapping to disk constantly. Going to 8GB helps a lot; the memory guide shows how to find out which type to buy.

Last resort: reset Windows

If it's still slow after all of that, and it has an SSD, years of accumulated software may be the problem. Settings → Update & Security → Recovery → Reset this PC, choosing "Keep my files," reinstalls Windows and removes every program. You'll reinstall the ones you use. Back up first regardless of what the option promises. And if you're resetting anyway, it's worth asking whether this is the moment to try Linux instead, which is lighter on old hardware and removes the Windows 10 deadline question entirely.

Product links on this page are affiliate links. If you buy through one, we earn a small commission at no cost to you, and the retailer's cookies apply once you're on their site (we run none). We link only to things that fit the advice above, and we never link to replacement computers as a fix for a working one.

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