CPU Keeps Jumping From 2% to 100% with every program

[iRixts]

My laptop (Dell Latitude D531) keeps lagging with every program i use even if i'm not using a program it wont stay at 0% CPU usage it keeps jumping from 2% to 100% without even opening a program, i tried every tip or trick and it never seems to work no matter what. I don't know if the problem is the Windows, The Fan, The specs in the laptop or even a virus although i scan it over 100 times but it never finds any problems, i tried playing games with the requirements super low example ( Pokemon using a gameboy emulator, super smash flash 2 and other low requirements games) and it runs smooth for at least 1 minute then it starts to move super laggy and when i watch the CPU usage its 100%, By any chance any one knows whats the problem cause, i don't have the money to buy a new laptop at the moment and want to enjoy the laptop till i get money for a upgrade.

 

[urbancamper]

Emulators are notorious for adding spyware. Some virus programs can hide themselves from virus scans. I am not saying you have a virus. but it is possible.

Does your antivirus have the ability to do boot scan? If you are using Windows Defender you need something better. Get Avast Free. If you only use it the one time it might be worth the effort. It has a very good boot scanner. A boot scanner, scans the system before any of the startup programs load. You can get it here. https://www.avast.com/en-us/index?ref=cj&utm_medium=affiliate&utm_source=commissionjunction&couponfield=yes

Obviously, this may not be the cause of your problems, but it is worth it to see if your virus scanner has missed something.

Also that laptop comes with a harddrive with very little room on it. I could be that the harddrive is near capacity and this could be the reason for it lagging.

The last thing I can think of since this is a very old laptop it could be full of dust causing it to overheat. That would cause lag, though it might not cause the cpu usage to jump up and down like that.