Thanks a lot for advice. I am not a pro, but in the past i have opened imacs. I know where the gpu located, i know how to replace it.
I don't want to spend money for the 6970 and finally doesn't work.
So that's why i asked "plug and play"..
I mean if i install the gpu and boot my imac, i will need something else to do? flash, etc or the card will work instanly, with bootscreen?
As for the heatsink, i will try to mod it. Temps are the second thing.
Thanks in advance and apologise for my poor english..