Just installed Window 7 on a computer build i did in April. Running Windows XP, the HDD led would flash every second. Kimsland helped me figure out what was causing and advised how to fix. After installing Windows 7, the HDD led is flashing again. Tried the Windows XP fix but doesnt work. The fix was change a Registry Key from a "1" to a "0". Changed it in Windows 7 but led still flashing. Disabled the (4) dvd burners in Device Manager, and the led quit flashing. This is not a critical problem... just aggervating.