EVGA 01G-P3-1080-TR GeForce GTX285 for Mac 1024 MB DDR3 PCI-Express 2.0 Graphics Card GeForce GTX 285 for Mac 1 GB with 648 MHz core clock PCI Express 2.0 1024 MB 512-bit GDDR3 memory 2484 MHz memory clock and 1476 MHz shader clock Open GL optimization and support