How to Speed Up a Slow Windows PC

A slow Windows PC almost always has the same few causes: too many programs launching at startup, a drive that’s nearly full, background processes quietly consuming RAM and CPU, or hardware that has simply hit its ceiling. The good news is that most of these are free to fix and take under 30 minutes to work through.

These 12 fixes are ordered from quickest to most involved. Start at the top and stop when the PC feels fast enough.

1. Disable startup programs

This is the single most common cause of a slow boot and a sluggish first 10 minutes of use. Every app that launches at startup competes for CPU, RAM, and disk access while Windows is still loading.

Open Task Manager (Ctrl + Shift + Esc) and click the “Startup apps” tab. Sort by “Startup impact.” Disable anything you do not need the moment you sit down. Common high-impact offenders: Discord, Spotify, Teams, OneDrive, Steam, and any manufacturer utility (Dell, HP, Lenovo apps you never open). These can add 30+ seconds to boot time individually. Disabling them does not uninstall them — they just won’t auto-launch.

2. Check what’s eating RAM and CPU right now

While Task Manager is open, click the “Processes” tab and sort by CPU, then by Memory. Look for anything consuming a large share when you are not actively using it.

Common culprits: browser extensions running in the background, antivirus doing a scheduled scan, Windows Update downloading in the background, and cloud sync tools (OneDrive, Google Drive, Dropbox) doing a large sync. If you see something you don’t recognize consuming significant resources, right-click and search online before killing it. If you recognize it and don’t need it, uninstall it entirely rather than just closing it.

3. Run Windows Update (and update your GPU driver)

Outdated drivers — especially GPU drivers — cause stuttering, poor frame times, and general sluggishness that looks like a hardware problem but is actually a software one. Go to Settings › Windows Update and let it run. Then check Device Manager › Display adapters › right-click your GPU › Update driver.

For NVIDIA, use GeForce Experience or download directly from nvidia.com. For AMD, use AMD Software: Adrenalin Edition. Intel Arc users should use the Intel Driver & Support Assistant. These tools install cleaner driver packages than the generic Windows Update versions.

4. Clear temp files

Press Win + R, type %temp%, hit Enter. Select everything in the folder (Ctrl + A) and delete it. Skip any files that are currently in use — Windows will warn you. This folder accumulates gigabytes of junk over time and costs you nothing to clean.

Also go to Settings › System › Storage › Temporary files. Windows will show you how much space is being used by temp files, Recycle Bin contents, and other categories you can safely delete. This takes 2 minutes and often frees up several gigabytes.

5. Check drive space

Windows needs roughly 15% free space on the OS drive to operate well. When a drive is nearly full, the system struggles to write temporary files, virtual memory, and update packages. Open File Explorer, right-click the C: drive, and check Properties.

If you are below 15% free, start trimming. Enable Storage Sense (Settings › System › Storage › Storage Sense) to automatically clean temp files and empty the Recycle Bin on a schedule. Manually uninstall apps you have not opened in six months — games especially. And move large media files (videos, photos) to an external drive or cloud storage.

6. Disable visual effects

Windows 11 has a lot of animations: fade effects, shadow rendering, smooth-scrolling, transparency in the taskbar and Start menu. On newer hardware these are invisible overhead. On older hardware they actively slow down the UI.

Search for “Adjust the appearance and performance of Windows” in the Start menu. In the dialog that opens, choose “Adjust for best performance” to disable everything, or manually uncheck the animations you find most annoying. The UI will look more like Windows XP, but it will feel noticeably faster on hardware from 2017 or earlier.

7. Change your power plan

Open Control Panel › Hardware and Sound › Power Options. If your PC is set to “Power saver,” switch it to “Balanced” or “High performance.” Power saver mode throttles the CPU to reduce energy consumption, which tanks performance in ways that are hard to diagnose if you do not know to look here.

On a desktop: High performance is fine. On a plugged-in laptop: Balanced is usually the right call (High performance generates extra heat without much practical benefit for everyday tasks). Never use Power saver on a plugged-in machine.

8. Scan for malware

Malware often runs persistent background processes that consume CPU and network bandwidth continuously. Open Windows Security (search for it in Start) and run a Full scan. This takes 30–60 minutes but checks every file on the system.

For a second opinion, download Malwarebytes (the free version is enough for a one-off scan) and run it after Windows Security finishes. The two tools use different detection databases, so running both catches more than either alone. If either scan finds something, follow their removal instructions before doing anything else on this list.

9. Defragment your HDD (but never your SSD)

If your PC still has a traditional spinning hard drive (HDD), fragmentation is a real performance problem. Files get written in scattered chunks across the disk, and the read head has to physically seek to each piece. Windows can consolidate them. Search for “Defragment and Optimize Drives” in Start, select your HDD, and click Optimize.

10. Upgrade to an SSD

If your PC still boots from a spinning hard drive, this is the single highest-impact upgrade you can make — bigger than more RAM, bigger than a faster CPU in most cases. Boot time drops from 60–90 seconds to 10–15 seconds. Apps open instantly. The entire system feels like a different computer.

A 1 TB SATA SSD costs around $60–80 in 2026. Most PCs that are 5–10 years old can take a SATA SSD without any other hardware changes. Migration is easier than it used to be: Macrium Reflect (free) clones your existing drive to the SSD sector-by-sector so you do not have to reinstall Windows. Swap the drives, boot up, done.

If your PC has an M.2 slot (check the motherboard specs), an NVMe SSD is faster still and costs only slightly more. For most people, any SSD is a massive improvement over an HDD — the difference between SATA and NVMe matters mainly for large file transfers and video editing.

11. Add more RAM

If Task Manager consistently shows 80% or more RAM usage during normal work — not during a game or video export, but just browsing with a few tabs open — more RAM will help. Windows starts using the page file (virtual memory on disk) as overflow, which is dramatically slower than actual RAM.

Most Windows PCs run well with 16 GB. 8 GB is tight for anything beyond basic use in 2026. Before buying, use CPU-Z (free utility) to check how many RAM slots your machine has and how many are occupied. If both slots are full with 2×4 GB sticks, you would need to replace both to upgrade. If one slot is empty, you can add a matching stick. Check your motherboard specs for the supported speed and generation (DDR4 vs DDR5).

12. Fresh Windows install

After years of accumulated software, registry changes, background services from apps long since uninstalled, and driver debris, a fresh install is often the fastest path back to a snappy system. It sounds drastic but Windows has made this much easier.

Go to Settings › System › Recovery › Reset this PC. Choose “Keep my files” (removes apps and settings, keeps personal files) or “Remove everything” (full wipe). Before doing either, back up anything important to an external drive or cloud. The “Keep my files” option is not a substitute for a real backup — treat it as best-effort.

After a fresh install, be selective about what you reinstall. Many slow PCs got that way because every piece of software the user ever tried is still running background services. Start minimal and add only what you actually use.

Where to start

If you have 15 minutes right now: do Steps 1–4. Disable startup programs, kill anything hogging Task Manager, run Windows Update, and clear temp files. That covers the majority of software-side slowdowns for free.

If the PC is still slow after that, Step 10 (SSD) is the best money you can spend on an older machine. The impact is immediate, the migration is straightforward, and a $70 drive can make a five-year-old laptop feel new.

Step 12 — the fresh install — is the last resort. It works, but it takes half a day to get everything set back up. Save it for when nothing else does the job.