Big Sur on iMac 27", Mid 2011, flashed 4GB NVIDIA Quadro K4100M by Nikey22, having issues with screen brightness, any ideas? Brightness control was working with Catalina Patcher, after installing Big Sur
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2GB Graphics Video Card HD6970M Replacement, for iMac Mid-2011 27 Inch A1312 Desktop PC Computer Core i5 MAC814LL/A MC814, AMD Mobility Radeon HD 6970M GPU Upgrade MXM Board Repair Parts
2011 iMac 27″ K1100M Graphics Card Swap And Install Catalina – TuXxX Blog
For iMac 21.5" A1311 Mid/Late 2011 6770 AMD upgrade Nvidia K610m 1GB Video Card | eBay
Intel iMac 27" AMD Radeon 6970M 1GB Video Card, Mid 2011 DIY Parts replacement Video Cards
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Picked up this iMac (27", mid 2011) i7 @ 3.4GHz , 16 gb ram , 256 SSD in excellent condition for $210. Should I make any upgrades ? GPU, bigger SSD? Thanks : r/LukeMianiYouTube
GPU ATI 216-0811000 Graphic Video IC Chip for iMac 27" A1312 (Mid 2011)
SOLVED: What GPU's are compatible with iMac 27" 2011? - iMac Intel 27" EMC 2429 - iFixit
2011 iMac 27″ GPU failure Fix/Upgrade – JCYCLE
How to Upgrade/Replace GPU Graphics Card on Mid-2011 21.5" iMac - YouTube