My computers performance is getting worse and worse

Last month my 4 years old acer laptop is experiencing serious performance problems(in simple tasks). I installed the latest version of bitdeffernder and found no viruses. Any suggestions?

 

If you had not reinstalled Windows (or used eRecovery to restore the notebook to factory state) in that time, it's time you do it.
Windows doesn't usually last that long without suffering performance issues.

Just make sure to back up your data on an external HDD before you attempt to do this.

Also you could have been more specific about the exact model of the notebook, version of Windows and configuration (things like the amount of RAM affect performance too)

 

Cleaning the fan and the heat-sink, as well as repaste would help too.

 

Fisrt of all thanks for your replies. It is an acer aspire 5742G with 4gb ram. Most of the times when my laptop has performance problems my ram is full , I mean it is working on 100% with few apps open. I try to avoid reinstalling windows because I hate the procedure of installing again all the apps that are already installed

 

If RAM is 100% utilized than that's your problem. See what happens so using so much RAM in process manager.
No one likes reinstalling Windows but after a long time it might be the only way - anyway - let's follow up on the RAM issue for now. See what process or processes use so much RAM.

 

Are you using any professional programs, such as Adobe Photoshop or CAD software? Those are very "hungry" on the RAM. As downloads said, check your processes in task manager. If you`ll see, that one of the system processes utilizes all the RAM, than you have the virus or damaged system files.

The best option for you now is a clean install of the Windows.

 

I reinstalled windows and everything is working better. Thanks