EVGA GeForce GTX680 2GB GDDR5 DisplayPort DVI-I, DVI-D HDMI Graphics Card  for Mac 02G-P4-3682-KR Base Clock: 1006 MHz Boost Clock: 1058 MHz Memory Clock: 6008 MHz Cuda Cores: 1536 PCI-Express 2.0 2GB GDDR5 256bit Nvidia GPU Boost, Support for Concurrent Displays, Nvidia CUDA Technology, PCI Express 2.0 Support, OpenGL 3.2 Support, OpenCL Support Mac Pro (early 2008) or later, [Models:MacPro 3, 1 or later] with PCI Express 2.0 slot, Mac OS X v10.8.3 or later, Microsoft Windows 8/7/Vista/XP (Apple Boot Camp)