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Graphics card is dead. How to replace. What to replace with. Where to get replacement. 27" 2011 A1312. Thanks!!
I’ve had about five repaired personally with that program and an untold number from this site have used it. UPDATE I have had about 70% success reflowing the GPU with a hot air work station.
We don’t have a logic board replacement or a GPU card replacement guide. But this guide will get you 90% of the way: Installing iMac Intel 27" EMC 2429 Dual Hard Drive Kit. Once you get the logic board loose (Step 31) finish removing it from the system. Do make sure to use a ESD mat and proper ESD protection here! The GPU card can now be removed and here are the possible replacement units: AMD Radeon HD 6770 (512 MB of VRAM) - 661-5967AMD Radeon HD 6770 (1 GB of VRAM) - 661-5968AMD Radeon HD 6770 (2 GB of VRAM) - 661-5969
I had 2 GPUs from the exact same mode. both have no signal and the 3rd diagnostic led isn’t even turning on. i have tried working them with a hot station but still nothing. if anyone has any suggestions I would love to hear them. thanks
