3fingerpete :
I'm going to revive this thread since the fan blade carriage of my 6770 has fallen off the the heat sink. I'm waiting for the results of the warranty check (purchased less than two years ago) but I'm still exploring all the options.
I'm in basically the same boat. What did you find?
Well, what happened in my case is the donut shaped circuit board and electro-magnet assembly just dropped off the bracket that bolted the whole thing to the heat sink. I managed to tack the thing to the bracket with a dab of contact cement but that repair lasted just a couple of days. The bearings in the fan blade carriage have now seized up, also.
I visited Radeon's warranty page (www.xfxforce.com, registering is required) and filed a service report. After a couple of days they issued a Merchandise Return order for me. I spent yesterday cleaning the board as they suggested and I'm about to ship it off to their facility. That's my status up to now. I'll post again when I know something further.