Hi if it is coming from the hard disk, this may cure it. Go to the control pannel, then Hardware and Sound, Then Power Options, then select a power option that you use and click "Change Plan Settings", then click "Change Advanced Power Options". Select "Change Settings that are Currently unavailable" at the top of the window that pops out. Then go to the Hard drive dropdown box, and after the "turn off hard disk after" is also dropped down you will have the option to do that.
(solution posted by kevin on lockergnome.net) If that dioes not cure it, follow the suggestions from previous poster and have a qualified malware removal expert look into the issue,
polonus