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The #1 Reason Your Computer is Slow

And what you can do about it.

There is one common reason computers slow down over time. The good news is, it's often within your control.


Perhaps the #1 complaint among computer users is that their computer is running too slow, or takes too long to start up, shutdown, or just “do things”.

Obviously, there are many possible reasons, but in my experience, one reason stands out above all others.

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The reason your computer is slow

The most common reason a PC might be slow is that there is too much software running — much of it starting automatically when you sign in. Uninstalling software you don’t use, avoiding unnecessary installs, and possibly disabling auto-start entries are the first steps to regaining control.

Too. Much. Software.

In my experience, this is the single most common reason computers run slowly.

There are simply too many programs running. There are so many that the program you want to use is competing with all the other programs for system resources, and as a result, it appears to be slow. Sometimes very slow.

Sometimes the program “competing” with all the software running on your machine is Windows itself. The result? Windows is slow.

This is a common scenario in computers that have been in use for “a while”. One reason new computers often feel so much faster — even when running on identical hardware — is that they’ve not had all this additional software installed.

So where does it all come from?

There’s one major culprit: installing software.

Installing shouldn’t hurt, but…

Installing software should be benign. Most of the time, it is.

Installing software shouldn’t cause it to run automatically when you turn on the computer — it should just place the software on your machine in such a way that you can run it when you want to.

Many software packages include components that run automatically when you log in or when Windows starts. Sometimes they’re legitimate components. Dropbox, for example, needs its component running to provide the services for which people use it.

On the other hand, many installs include auto-start components that, at least in most people’s opinions, are completely unnecessary.

Microsoft Office used to install what they called its “quick launch bar”, which ran on login. Its job was to pre-load portions of Office just in case you were going to use them. The reality, though, was that the quick launch bar slowed down startup and other applications. Yes, Office programs appeared to load more quickly, but at a cost.

Those are just examples. There are literally thousands of different things that could affect your computer’s speed by running automatically without your knowledge.

What to do

  • Don’t install software you don’t need. The people whose computers have the most serious problems are often those who like to try things out. As a result, they install software after software after software … and then end up wondering why their computer takes forever to start and runs slowly when it does.
  • Uninstall software you don’t use. The good news is, I’d say 90% of the time programs that install software that runs constantly in the background also uninstall it cleanly if you uninstall it.
  • Turn off auto-start options. Many programs allow you to control whether they start components at Windows startup or user login. Check the Preferences or Options in those programs for settings you can control, and turn off any auto-starts you can.
  • Review what’s in the notification area of your taskbar. The notification area — that area to the bottom right of the taskbar — contains icons of software running in the background on your machine. Consider whether running that software is necessary. If it’s not, uninstall it, or check in the application for an auto-start option to turn off.
  • Examine what else is auto-starting. Using tools like autoruns or the Startup tab in the Windows Task Manager, you can examine what starts automatically on your computer. Don’t just turn things off; use what you find as a basis for further research to determine exactly what that program is and whether you need it.

The extreme solution

This problem isn’t new. Speed and stability declining over time have plagued computers since their invention. It’s sometimes referred to as “software rot” because the implication is that things just get worse over time.

There’s also a long-standing solution that isn’t as piecemeal as what I’ve discussed so far:

  • Back up.
  • Reinstall Windows from scratch, formatting or erasing the disk as part of the process.
  • Install only the applications you actually need.

The result is a faster machine simply because you didn’t reinstall all that old stuff you weren’t using.

Do this

It’s tempting to have lots of things on your machine “in case” you might need it someday. I do it myself. But over time, particularly if you find you’re not using what you installed some months or even years ago, it’s time to uninstall. It’s also a great time to reconsider whether installing software just in case you need them in the future is enough of a criterion to install additional tools now.

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15 comments on “The #1 Reason Your Computer is Slow”

    • There are MANY places that there are “auto start” entries. The two mentioned in the article are the easiest to deal with: “start with Windows” settings in each of the various apps you have installed, if they have such a settings. Turn that off, and you can always turn it back on later if you need. Then Task Manager, Start Up tab — set items to “disabled”. You can enable them later if you need.

    • If you really, really want to get into it: First, there are downloadable programs online which will itemize and list all processes that are running in the background. Download these at your own risk. There is one reliable Microsoft set of tools called System Internals. This includes an application called autoruns, which will list most things loaded in memory and running. You can also look at the startup tab of “msconfig”, which is a Windows utility that allows access to some system details. Then you can look in the Windows Services to see what is started and what is set to start automatically. But that’s not the end of it. There are many places in the Windows Registry that are set to initiate processes. Obnoxious applications (including websites) that insist on always running on your computer will embed start-up triggers in many places so that if you delete one others will take over. In extreme cases you may have to find and delete the executable or DLL files that causes processes to run in the background. It’s a cat and mouse game and you need patience and good level of knowledge to keep junk from running on your machine. Caution: your can really break your system if you’re not careful, but investigating these is a good learning experience.

      • “Caution: your can really break your system if you’re not careful, but investigating these is a good learning experience.” Absolutely. Solution: back up before starting this process. Although, there’s no real danger in disabling a program that you end up needing. You can always enable it again. Back up anyway.

  1. Ok Ok I see now that Leo Took the time to respond back “(start with Windows” settings in each of the various apps you have installed,)” My Bad. Thanks Leo !

  2. Another place to look is Startup in Settings. Press the Windows key an start typing “Startup” without the quotes and click “Startup apps”. Also under “Apps and features” you can click on ” Optional features” and you might find some Windows apps you can uninstall.

  3. I have done the “re-install windows from scratch” option recently, and it does indeed work. I managed to get more use out of an ageing i3 this way.
    Something I’ve also done to breathe life into older machines, is simply add some memory. Win10 needs more memory than the Win7 it typically upgraded from in our office, and I found upping the memory from 4gb to 8gb worked wonders.

    • I had a useless Android phone. It would run the battery out in a couple of hours, even a brand new battery. I reset the phone to factory state and the battery now lasts a day and a half and is much faster. Works for phones and tablets as well as computers.

  4. Very good points, Leo. But still begs the question – I look at the Autoruns list, and it’s huge. Okay, some stuff I see that obviously needs to keep running in the background. A few things are clearly garbage (GI,GO ). But most of it is unclear. How does one *know* if a program really needs to autorun. Many of these are programs I do need, but maybe only get used once every five months or so. Do I *really* need MS Visual Studio Time Adaptor Add-in listed ten times under autorun? Aargh… I’m getting a headache!

  5. Well I speeded up my 2009 DELL Inspiron 545 desktop by doing a “Reset this PC” and re-installed a clean version of Windows 10. It seems a lot spritlier now.

    But, and this in the mother of all buts: When the rest was completed and W10 relaunched my mouse and keyboard were ‘dead’. I could not get in to perform any troubleshooting. I used my smartphone to view the forums and another user suggested plugging my wireless Transceiver into a USB (Belkin) adapter. Strangely that worked and my wireless mouse/kbd is working form the adapter socket.
    I now need to find out what happened to my USB slots after the W10 re-install and plug my transceiver back into the original USB socket ( at the rear).

  6. I try out a LOT of software, so I’ve developed a system to keep track of what I have installed on my computer. First, I keep a software log (A LibreOffice Writer document). When I install a new (to me) program, I record its name (green text), state (installed), install date, and download URL (each item on a single line) so the apps on my system each get their own ‘paragraph’ separated by a blank line.

    The first day of each month is my System maintenance day. I keep a list of System Maintenance Routines (things to do monthly, so I don’t forget any of them). One of my ‘routines’ is to look over my apps log. If I see an installed app I have not used in the past month, I remove it for my system, changing its state to ‘removed’, and the name’s text color to blue (so I can see its state visually). When I see a listing for a program that has been removed for more than a year, I remove it from my list, except its name (so I know I’ve had it installed/removed before).

    I store these two files along with several others in a maintenance folder on OneDrive to maintain a record of what’s on my system and what’s been done to it over the months and years (well, actually the past year – I don’t see any point in keeping records older than that).

    I have found that by keeping my system free of unused programs, it seems to have kept its original performance since I developed this system. Side note1, another of my monthly routines is to run a disk cleanup (using the feature included with Windows). Side note2, since I have developed my maintenance system, I have not had any functional issues either. No problems with system updates. No mysterious errors I cannot explain. Everything seems to run very smoothly, so for me, it has been worth the effort. If you cannot do something similar on the first day of the month, maybe you can do so on the first Saturday or Sunday of the month. You might be surprised how much better your computer works.

    I hope this helps others,


  7. Hi, there are many things you can uncheck in Win 10 in Settings to accelarate your computer. For example in System go to Notifications & actions, there uncheck all the blue marked boxes, that is set them to OFF and go on unchecking all the other boxes. I find all those items unnecessary. Then go to Gaming, there set it to OFF and uncheck all other boxes. In Personalization go to Start, there uncheck all items. Now go to Lock Screen, there under Advanced slideshow settings set it to OFF, at the Choose apps etc, click on every box and select NONE. In Privacy under General uncheck all boxes. In Notifications uncheck all. You could go on unchecking different settings at your own risk. I also go to Services (This PC>Manage>Services and Applications>Services) and stop many services that are automatic, and set them to Manual or Disabled, for example: Sysmain if you have an SSD installed, Search if you have a slow microprocessor and not much RAM, all the Xbox services, etc, you can disable program updates from here that start with Windows. In the Task Manger under Sartup you can disable many programs from starting with windows. If you download Autoruns, it belongs to the SysInternals suite, you can disable many more things, you also can do this with CCleaner. If you download Quick CPU, you can optimize some processes of you microprocessor. You can also use Speedyfox to accelerate all brousers. Type MSCONFIG in the search bar, System Configuration opens, once there select Boot, now click on Advanced Options, now click on Number of Processors, set it to the maximum, close and your done, next time you start your machine it will start much faster. I’m sure there are many other things you can do, as mentioned by other readers tuning the registry. Hope that was helpful.


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