Any ideas why my system periodcally locks up/crashes either at night or while I am at away at work? This might happen 2 nights in a row then not again for a week - no pattern at all. I have power options set to 'balanced' . 'Put computer to sleep'>'Never' (on main page), 'allow hybrid sleep'> 'On' (advanced settings), 'turn hard drives off' > 'never'. I have automatic back up set to run each night at 10:00 to an internal HDD, but other than that the only things that should be running are the defaulted Windows 7 settings such as updates, etc.