Further to my above post, I am now getting blue screens and reboots. Tried to uninstall the drivers which has made the problem worse. Back to the drawing board and doing a complete reinstall after a system restore didnt work. It appears that the video and audio drivers are possible not compatible with this system set up.
If anyone has a solution, I would love to hear it.
After a full reinstall of my system and using the default drivers windows installs and not the ones supplied on line by intel, my system seems to be stable (so far). Anyone who buys this board and installs needs to remember not to upgrade to the online intel drivers.
As a side note for toslink connection using the default Windows 7 drivers - There are 2 options for the S/PDIF out in Playback devices. If you are using soundgraph imon tool (i.e. on an antec media center) you will need to fiddle to get the volume control on your remote working in media center by selecting the correct one of the 2 options in the imon manager and then the same in playback devices.
Hope this helps someone else