I believe Alienware you cannot open the case you need to RMA whole machine.
Do you know any A+ certified technichians that can help you? I am a tech but I don't think you should if you do not feel confident. This is a very easy fix but I think maybe Nvidia Vendors should Recall the cards or release a solid guide for the fix I have tried the fix on 5 different brands of the 6800 series cards all with the same result. Nvidia's tork specs are incorrect or just sloppy manufactureing on the Vendors behalf but it is conclusive that these cards are overheating not beyond spec but the cooling solution is to blame.