Respuesta a "What GPU's are compatible with iMac 27" 2011?"Interesting..... My iMac from the same series went in just last week because the 2Gb card died. Apple Store was very good and said even though it's outside the replacement program dates (it was purchased in Aug 2011), they would cover the cost. It's taking a little longer than their usual timeframes for repair waiting for the part, but at least I'm not out of pocket for the repair (about the same cost as the lowest end iMac). Mind you, our consumer protection laws in Australia are very good and given it was a known issue to this model Apple may not want to test the laws with a denial to repair.