I have AVG Free and it got rid of a svchost.exe virus that was using up almost 98% of my cpu and it didnt have any services connected to it so I knew it was a virus hosting itself as a svchost.exe. I used avira,spybot,windows defender,malwarebytes,and norton and none of them could even detect the virus except AVG Free
Try out AVG if none of the other recommendations have not worked yet