How to fix a slow computer

A computer being slow can be caused by any number of things, clutter, malware(see more on removing malware here), age.

The culprits

1. Clutter



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• Clutter is a very common cause of slow computers, and comes in a few forms
1. Desktop clutter as seen in the picture above is a heavy factor in causing slow systems for getting rid of it I suggest deleting all folders and files that don't need to be there, and making a folder for files and folders you want to keep.
2. Program clutter can cause slow systems too this happens when you have too many applications installed, the age factor comes in here again. For getting rid of Program clutter I suggest uninstalling any programs you no longer use
• To uninstall programs in windows 7 
1. Click Start Menu > Control Panel .
2. If you are in Category View Click Programs > Programs and Features. 
3. Go through the list for programs you no longer use when you find one click the Uninstall or Uninstall/Change button. 
4. If you are in Icon View scroll down until you find "programs and features."
5. Click on it and follow step 3.
• To uninstall programs from windows vista
1. Click Start Menu > Control Panel .
2. If you are in Category View Click Programs > Programs and Features. 
3. Go through the list for programs you no longer use when you find one click the Uninstall or Uninstall/Change button. 
4. If you are in Icon View scroll down until you find "programs and features".
5. Click on it and follow step 3.
• To uninstall programs from windows XP
1. Click Start Menu > Control Panel.
2. Double-Click add or remove programs.
3. In the currently installed programs box find the program you want to remove and select by clicking it.
4. Click Remove.
2. Age

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• As a computer gets older it will inevitably get slower causes of this vary from just using it to hardware malfunctioning we're only discussing for the most part the software side of this, because I don't know what's going on with your computer so it'd be hard for me to diagnose it, and there are tons of hardware issues with older computers, so here I will discuss the best way's to help prevent age from decreasing your speed with software.
1. Defragmenting
• Defragmenting and doing so regularly can help keep your system running smoothly fragmentation happens when a computer cannot or will not allocate enough contiguous space to store the complete file as a unit, it puts different parts of the file in between gaps of other files the slowness comes when the computer has to read a file, but the parts of the file are scattered about so it takes time to find them all or in some really bad cases it cannot find them all, there's a free defragger I'd recommend, and it is Auslogic's Disk Defrag.
2. Upgrade your OS
• If you have an older computer chances are it's not running windows 7, and I'd advise you try to upgrade you can check if your computer can run windows 7 by going here.

In closing I just want to say I hope this helps you speed up your PC feel free to leave comments in the box, and I'll try my best to respond.