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How To Flash A PC GPU With A Mac ROM For Your Late 2009 - Mid 2011 iMac - YouTube
iMac 2009 / 2010 / 2011 GPU upgrade — Fixing LED/LCD PWM brightness with an ESP32 | by Fixing Things | Medium
iMac 2009 to 2011 (A1311/A1312) Upgrade Guide – MacintoshMen