Apple opens graphics card replacement program for some mid-2011 iMacs - 9to5Mac
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
Tarjeta gráfica de 2 GB GPU de repuesto para iMac 27 pulgadas mediados de 2011 A1312 computadora de sobremesa Core i5 3.1 MC814LL/A MC814, AMD Radeon HD 6970M GDDR5 2GB MXM Video
2011 iMac Graphics Card Upgrade | How to | Mac Expert Guide