Without a doubt it is graphics related. Providing you can see nothing else but the no signal message I would indicate the card is faulty.
If you can see your bios or part of the windows load then it could well just need drivers to be to reinstalled.
It sounds like your card is PCI Express? so I doubt you would have one spare. If the card is under warranty, then speak to the suppliers/manufacturers.
If its not under warranty then a cheaper solution would be to buy a new card.