Keystroke lag problem: My HP laptop running WIN7 intermittantly has keystroke lag problems, i.e., i type a letter and it will not show/be visible for a few seconds. This problem always happens when I can hear, what I assume is, the hard drive whirling. I've looked at Task Manager during this problem period and nothing jumps out at me. When the hard drive goes quiet, the delayed keystroke problem goes away.
I've read several past posts regarding this problem, but given my limited knowledge base, I'm not able to figure out a solution. I've run virus, malware scans, nothing seems to help. Any suggestions would be much appreciated.