Computers tend to slow down over time as hardware ages and hard drives become cluttered with data. Paying to upgrade hardware such as RAM, hard drives, or video cards is a common way to increase computer speed, but there are several ways to optimize a computer and increase speed without spending money.

Resource Usage

Computers have a limited amount of hardware resources that can be used toward running programs and processes. Attempting to run many processes at once is hard on a computer's memory and processor which can lead to slow operation. Avoiding running more than one program at the same time can help speed up computer performance. Shutting down processes that are not being used can also increase speed. Computers often launch several unnecessary programs at startup such as video player applications, instant messengers or other programs that the user may have installed. Close these programs or disable them from the startup process to help increase speed.

Hard Drive Maintenance

The hard drive contains all of the data required to run a computer's operating system and programs. When the hard drive becomes full, it may take longer for it to access data, which can lead to computer lag. Deleting old unused programs and media files can help clear up hard drive space and reduce lag. Running a hard drive defragmenter tool at least once a month is also a good idea. Defragmenters rearrange data to make it easier for the hard drive to access it. If you store a large amount of data on the hard drive that you don't want to lose, such as personal videos and photos, consider backing them up on an external hard drive and then deleting them from your main hard drive to free up space.

Remove Malware

Malware are programs that can damage a computer. If you are infected with malware, your computer may run slower, since the malware might run unnecessary processes or interfere with your computers normal function. It is important to run an antivirus program at all times while on the internet to avoid malware infection and to scan your computer for malware at least once a week. Although certain anti-virus programs cost money to subscribe to, there are several free options, such as AVG Free, Avast and AntiVir. You should also consider using free spyware and adware scanning tools to conduct addional scans on your computer for another layer of security. Ad Adware and Malwarebytes are two free anti-malware scanners to consider.

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I had the same problem. This is what I did: First of all remove all the big files from your desktop. If your hard disk is full get some external usb hard disk and move all your movies and pictures there. Then update you antivirus and antispyware and run a full scan. After that a defragmentation is a good idea. If the problems still persist then you should use a decent registry cleaner. If you are not sure which one to use maybe you could do what I did. Visit the http://thebestofregistrycleaners.com They should be able to help you. I would advice you not to temper with your registry.