Windows 7 comes with a variety of different power saving features which can cause issues if a system is overclocked...
These are the best Settings to use for stability
Right Click desktop & Select - Personalise
Select - Screensaver
Set Screensaver to - Never
Click - change Power settings
Click - Create a High Performance Power Plan (Call it Overclock)
Click - Next
Set - Turn off display Never
Click - Create
Make Sure Overclock Plan is Highlighted and Click - Change Plan Settings
Then click - Change Advanced Power Settings
This is where all the hidden options are that need to be disabled...
Click + Next to Hard Disk and Set Turn off to Never
Click + Next to Desktop Background Settings and Set to Disabled
Click + Next to Sleep & Set Hybrid Sleep Option to Off
Set Hibernate to Never
Set Allow Wake Timers to Disabled
Click + Next to USB Settings & USB Selective Suspend set to Disabled
At the Bottom of the List Click the + Next to Multimedia SettingsClick the + Next to When Sharing Media & Select Prevent Idling to sleep
Apply the options and your done
There you go you should have an Insomniac 3XS system after applying these settings