Different programs call this different things (AVG - "Resident Shield", etc..) but it is basically a program that runs in the background checking each and every file that gets read as you use your computer. This may not seem like much but most programs actually reference many files during normal operation (some, over and over again) so your computer can get dogged down in a big way. When people complain about their computer running slow, this is usually the problem.
It's usually easy to disable: open your virus program and locate the real-time checking feature and disable it.
|Program||Real-time Checking Feature Name|
Most virus's get on your computer from email, web browsing and on installing programs. You always want virus checking on email and web browsing, and when installing programs, always check the install file for virus's before installing (save the "install/setup" file to your computer and run a virus check on it first).
This is another common reason for computers to slow down: low disk space. Disks are like little neighborhoods of storage units. Unfortunately, most files will not fit in a single storage unit so they must be broken up into pieces and saved in separate storage units. If you were putting your personal belongings into storage but needed more than one unit, it would save you a lot of time if the units were right next to each other. Operating systems such as Windows, Mac and Linux have the same problem when saving files. If a file can be saved in adjacent storage units, they can be moved MUCH faster. When a disk starts getting full, the operating system has to save the file fragments in different areas of the disks making take a lot longer to reassemble the file for use by a program.
You'd think that this wouldn't be a problem unless you were actually performing a "Save" operation but operating systems are constantly reading and writing to the disk even when you are not saving a project file. In order to make programs more upgrade-able, they are broken up into smaller sub-programs that are stored in separate files that only get read when they are needed. If these files are broken up into fragments that are scattered around your disk, it will take the computer longer to read them.
As a very rough guide line, a typical computer should have at least 5 Gig of free disk space to operate optimally. If you have less than 5 Gigs of space left, you are probably going to experience some slow down of your computer depending on the particular operating system (Windows, Mac, etc..) and what programs you have installed.
|Use||Free Space (minimum)|
|General use||5 Gig. 10-20 Gigs is better|
|Edit/save pictures||50 Gigs|
|Audio recording||50-100 Gig|
|Video editing||100 Gigs|
On Windows computers, this disk space is easy to check:
Computer disks are really organized like little towns with people's possessions/files stored at unique addresses. If you think of the town as being filled with warehouses, you'd realize that size of each warehouse determines how much stuff will fit in it. You'd also realize that really big things won't fit in a single warehouse and need be taken apart and stored in multiple warehouses. This happens all the time on disk drives but only becomes a problem when things have to be stored in warehouses in different neighborhoods. It takes time for your moving truck to drive to each of the locations to pick up a piece of your big file. And the longer you use a disk drive, the more moving that is going around so the neighborhoods tend to get filled with fragments of files which take a long time to reassemble. Things get tricky when someone moves into the warehouse next to yours and you buy something that you don't have room for in your current warehouses. You'd prefer to use the warehouse right next to yours but it's filled so you have to go find an empty warehouse somewhere else. Again, this is happening all the time cause the disks to become more and more fragmented over time.
Defragmenting your disk drive is like having a team of movers come into town and moving everyone's stuff around till everyone's belongings were all stored in adjacent warehouses. It's time consuming so you don't want to do it constantly, but can really speed up the access to files which is one of the major causes for computer slow downs.
For more information about how disk drives work, check out the Disk Drive article on Wikipedia.
There are so many great (and sometimes free) programs out there that are easy to install, our computers end up with lots of programs that we don't use but which still slow our computers down. Many programs only use your computer's power when the program is open but many programs install little sub-programs that run in the background slowly absorbing tiny bits of your computer's power. Usually they use so little power that you wouldn't even know they were running but they do accumulate and can even result in pop up messages at inconvenient times ("Sorry to interrupt your recording session but do you want to install the latest version of iTunes?")
Uninstall programs you don't think you'll ever use. This will eliminate them from possibly slowing down your computer and free up disk space in the process. Also, disable "Check for updates" features.
Some viruses don't completely shut down your computer but instead, send your computer off doing some evil bidding on behalf of author without your knowledge. Your computer might be spamming millions of people without you knowing about it. It's best to set up a weekly system scans for some time when you don't expect to be using the computer (scans can take hours and will slow down your computer if you use the computer while the scan is running).
Most internet providers provide free virus protection (Comcast - McAffee) but there are plenty of other free and inexpensive alternatives. See our Antivirus articles for more.
If there is a disk on your computer that went bad ("Needs to be reformated"), there may be programs that are still referencing files on the bad drive. The operating system keeps trying to find the file on the disk and keeps timing out slowing your computer to a crawl (This recently happened to us).
The solution is pretty easy: power down the computer and disconnect the bad drive. You can often recover data from these disks using something like R-Studio File Recovery Software but if the operating system is convinced there is something on the drive it needs, the computer will be unusably slow. It's best to pull the drive out and install it in an external drive chassis (USB) for recovery process. This changes the drive letter so the operating system doesn't keep banging its head against the wall.
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