Unwanted task manager processes

hi guys, I checked my task manager, I have like 12 svchost.exe running and one of them is hogging memory. They exist since I format my harddrive last week so I don't think infections have anything to do with them. Anyways I still run a full scan with avg and no suspicious result return. I remember I used to have only 5 svchost.exe running. Can I remove disable some of them? How should I do...