Have the same problem. At random times my Disk Usage would go all the way up to 100%. Using Windows 8.1. I WOULD LOVE to downgrade to 7, but computer has no "official" Windows 7 drivers (HP Pavilion p6-2327c desktop); therefore, I would have to hunt down USB, Sound, Graphics, and many I/O drivers. Just have to stick with 8.1 for now.