Chosen Solution
Hi, I have a 2011 27” iMac with the AMD Radeon HD6770 512MB GPU that stop working properly. I want to change it so I can also get an upgrade with the AMD Radeon HD6970 2GB. I know this card works on my iMac but the heatsink looks larger because the card itself is larger than the HD6770. Do I need to find and replace the heatsink for one that is for the HD6970? Thank you very much for your time. Have a great day and stay safe. BTW: I have already try the baking method on my old GPU, but I don’t know if my oven was not good or the card is just bad after I send it for maintenance and when I open it, one screw was off and I think that might ruin the old GPU. I had it work for 2 days after baking XD was fun while it last. Now is back on box and hope to replace it ASAP.
The 27” GPU heat sink is quite large and is the same size across all of the GPU options. The 21.5” GPU heat sink is smaller! Did someone put in a 21.5” heat sink instead of the proper one?
The 27” heatsinks are not all the same. For a 2GB card you would want the 3 pipe variant of the heatsink otherwise you risk cooking your card.
