I have a late 2011 15" MacBook Pro with 2.4 GHz CPU and AMD 6770M GPU. The GPU is dying and I want to get it repaired. I found some listings for repair service on ebay, but I don't know what the part number for my MBP is. Is it any one of these? * A1286 820-2915-B * A1286 820-2915-A * A1286 661-6162 661-5852 Or is it something else?