You could try the repair shop although there is a good chance they can't repair it. You would void the warranty by doing so, however. So if the repair shop tries and fails, you might have to pay the manufacturer to repair it or eat a dead card. IMHO, you'd be much better off sending it to the manufacturer to begin with.
Are you sure it is the video card and not a power supply that isn't up to powering new, more powerful card?