Update:
Tried again without the wireless card, no joy.
Likewise I reset the CMOS without any results.
Also removed the usb devices without getting video out.
Referring back to the speaker question from earlier, whilst the mobo doesn't have a built in speaker it does have the pins to allow one to be attached. I'll pop into a store tomorrow if I have the chance and pick one up. Would that rule one way or another if the mobo is the issue (i.e. if there are no beeps it's defiantly the mobo, etc.)?