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For iMac 27" A1312 Mid 2009 2010 2011 upgrade NVIDIA GTX 780M 4GB Video Card | eBay
How to Upgrade/Replace GPU Graphics Card on Mid-2011 21.5" iMac - YouTube
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iMac 2009 / 2010 / 2011 GPU upgrade — Fixing LED/LCD PWM brightness with an ESP32 | by Fixing Things | Medium
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