CPU usage 100% default.

[kedarjk]

Hi all,
Yesterday while watching movie on my desktop I observed that performance of my PC is very low.
So to just find it out, I checked in task manager. Surprisingly I observed that, CPU usage of my PC is 100% by default.
I closed many applications which were open, but still no change. Watching only a movie of .avi file type, is making CPU usage of 100%.
I asked my friend regarding this, he said it could be a kind of virus.
Anybody knows about this?
Any way to remove it out?

[ash]

Which process is utilizing the most CPU usage? Also, can please you list out a detailed specification for your computer?

[The_Big_K]

Yeah,

Right click on taskbar -> Task Manager -> Processes tab. Then look at the process which is eating most of the resources.

...then fire it

[kedarjk]

I tried ending some network processes, dur to which usage was high, but after that also, no change. Usage sticks to 100%.

Ash, its a 4-5 years onlder PC. PC config is Intel 845G-Celron-512MB RAM-80 GB HD.
Any other ways?

[gaurav.bhorkar]

Try to repair your Windows.
May solve your problem.

[ash]

It could probably be a virus like your friend said, some system files controlling Windows processes have become corrupted, or there are still a lot of hidden processes that are running. Also, if you have not done frequent file defragmenting, it would add some overhead to CPU.

Have you done a Virus and Spyware scan? The free AntiVir and MalwareBytes come in highly recommended. Others here have recommended Avast.

Also, use a program like CCleaner to delete all temporary files that may have accumulated over 5 years. When thats done, do a file defragmentation process using the default Windows Defragmenter or the powerful JKDefrag program.

If things still do not fare well, reformat the computer. Though, this would be a desperate case only.