Windows 11 Slow & Laggy? Fix!

Windows 11 taking forever to boot, apps hanging on launch, and the whole desktop stuttering when you alt-tab usually comes down to a handful of things: too many programs auto-starting, a power plan that throttles your hardware, a nearly full system drive, or outdated graphics drivers. Work through the steps below in order - each one targets one of those causes, and most machines feel noticeably faster after the first three.

Why this happens

Every app you install quietly adds itself to startup and background tasks, and Windows 11 also ships with visual effects and a balanced power mode that trade speed for battery and looks. Over months this stacks up until the system feels sluggish even at idle.

What you'll need

Administrator access to the PC. No downloads are required - everything below uses built-in Windows tools.

Steps

1. 01
   Restart the PC fully (Start > Power > Restart, not Shut down - Fast Startup means Shut down keeps the old session), then install pending updates under Settings > Windows Update, since an update stuck mid-install will drag the whole system.
2. 02
   Press Ctrl + Shift + Esc to open Task Manager, go to the Startup apps tab, and set everything you don't need at boot to Disabled - especially updaters, game launchers, and chat apps with High startup impact.
3. 03
   Go to Settings > System > Power & battery and set Power mode to Best performance so Windows stops throttling the CPU at idle, particularly on laptops.
4. 04
   Press Win + R, run sysdm.cpl, open the Advanced tab, click Settings under Performance, and choose Adjust for best performance (or keep only Smooth edges of screen fonts checked) to cut the animation lag when opening windows.
5. 05
   Free up drive space in Settings > System > Storage: run Temporary files cleanup and turn on Storage Sense. Windows needs roughly 10-15% of the system drive free to page and update properly, so a nearly full C: drive will lag constantly.
6. 06
   Uninstall programs you no longer use from Settings > Apps > Installed apps, and for apps you keep but rarely need, open their entry's Advanced options and set Background apps permission to Never.
7. 07
   Update your graphics driver from the vendor's own tool or site (NVIDIA App, AMD Adrenalin, or Intel Arc Control) rather than relying on Windows Update, since old GPU drivers cause desktop stutter and slow window animations.
8. 08
   Run a malware check: open Windows Security > Virus & threat protection > Scan options and pick Full scan. Cryptominers and adware love to eat CPU in the background and are a classic cause of a suddenly slow PC.

Still not working?

If the machine is still crawling, check what is actually maxed out in Task Manager's Performance tab. Constant 100% disk usage on a hard drive means the drive itself is the bottleneck - moving Windows to an SSD is the single biggest upgrade you can make. Memory pinned above 90% with a few browser tabs open means you need more RAM or fewer background apps. If CPU, disk, and memory all look fine but the system still lags, run sfc /scannow from an administrator terminal, and as a last resort do an in-place repair install from Settings > System > Recovery > Fix problems using Windows Update, which reinstalls Windows without touching your files.

Frequently asked questions

Will disabling startup apps break anything?

No - the apps still work normally when you open them, they just stop launching themselves at boot. Leave your antivirus, audio, and driver utilities enabled; everything else is safe to disable.

Does Windows 11 just get slower over time?

The OS itself doesn't degrade, but the pile of installed apps, startup entries, and background services grows with every program you add. Trimming those (steps 2, 5, and 6) recovers most of the lost speed without reinstalling.

Should I just reinstall Windows?

Usually not as a first move - the steps above fix most slowdowns in a few minutes. Reinstalling helps mainly when the install is years old and full of leftovers, and the in-place repair option mentioned above gets you most of that benefit without wiping your files.