Probably the same dies with one GPU core disabled. My guess is the GPU cores are large (== relatively likely to have a defect) and also easy to isolate. Apple h

Probably the same dies with one GPU core disabled. My guess is the GPU cores are large (== relatively likely to have a defect) and also easy to isolate. Apple has done the same thing for previous processors and it's pretty common practice across the industry. Eventually yields will go up and they might either make a pure 4-core version for lower end products or they'll just remove that from the line entirely.