I had to sort out a massivly overheating Kryo-2 once, and i sorted it quite easily. all you need is a old stock hsf combo from a cpu, 4 big cable ties, (lots of) cheapo *non conductive* thermal paste, some mineral oil and some fine muslin cloth.
(disclaimer : its not my fault if you do this and it blows up, it worked for me and cooled the card by about 10'C (btw.. yes, any warrenty will be void... whats that mean you ask? i dont know. i have never been able to use a warrenty in my life :P .))
first, get your muslin, and fold it into quarters, and cut it to the shape of the bottom of the heatsink, then cut along the folds so you have 4 peices of muslin. mix the thermal paste about 10/1 with thin mineral oil (hydrolic oil for a skip truck is ideal) and then soak the muslin it it, then line up the squares and place them on the heatsink. you need to compress them slightly, put a peice of paper or two on them and then stack about 5-6 floppy disks on top.
while they are setting up, you need to get two big cable ties and find a way to get them around the card so they dont interfere with anything else, but pass either side of the main hotspot on the back of the card (back of gpu usually) about the same width of the heatsink.
now, with the heatsink on the card, so the fins run the other direction to the cable ties, you need to pass each cable tie around the other 2 on the card and either side of one of the fins. do the same the other side, and pull them tight (Not too tight!!!)
now, fire that ghetto monster up and see what happens.
