EVGA GeForce GTX660 2048MB GDDR5 192-Bit, Dual DVI-D, HDMI, DP and 2-Way SLI Ready GPU Graphics Cards 02G-P4-2660-KR Microsoft DirectX 12 API (feature level 11_0) Support Base Clock: 980 MHz Boost Clock: 1033 MHz Memory Clock: 6008 MHz Cuda Cores: 960 PCI-Express 3.0 2048MB GDDR5 192-bit Nvidia SMX Engine, Nvidia GPU Boost, NVidia Adaptive Vertical Sync, Nvidia Surround, Support for Concurrent Displays, Nvidia PhysX, Nvidia 3D Vision Ready, Nvidia SLI Ready, Nvidia CUDA Technology