Posted 26 March 2011 - 03:11 PM
Open msconfig and on the General tab choose "selective startup" (disable everything from loading) and reboot. Does the problem still occur? If not, start adding items back to msconfig one or two at a time, rebooting after each change, until the problem reappears and you'll have identified the offending process. This is clearly a time consuming process, but it is the best way to determine if some process loading with the system is the cause of your problem.
If this method doesn't work, look in Task Manager to see if anything is scheduled to run in the background. Also check your av to see if it is set to run scans in the background. Also, you can open task manager to the processes tab, sort on the cpu column, and see if anything is using the cpu when the hd is active.
Last, if the problem still exists you should post in the Am I Infected forum on this site.