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I have a late 2009 IMac 27 inch 3.06ghz core duo CPU with a ATI Radeon HD 4670 256MB GPU. The GPU is going bad. Can I replace it with the ATI Radeon HD 5670M 500MB graphics card ?
Here’s a bit more on your boards: Used in the 21.5 & 27” Late 2009, Mid 2010 21.5” iMacs: ATI Mobility Radeon HD 4670 Apple P/N 661-5308Used in the 21.5 & 27” Mid 2010 iMacs: ATI Mobility Radeon HD 5670 Mac Edition 256MB board - Apple P/N 661-5539, 512MB board 661-5546 Another option is going with this board: Used in the 21.5” Mid/Late 2011 AMD Radeon HD 6770M, 512MB, Apple P/N 661-5945
