Zotac GeForce GTX 660 2GB GDDR5 PCI Express 3.0 HDMI DVI DisplayPort SLI Ready Graphics Cards ZT-60901-10M 960 processor cores, 192-bit memory bus, Engine clock (base): 993 MHZ, (boost): 1059 MHZ, Memory clock: 6008 MHz, PCI Express 3.0 (compatible with 1.1) Display Port 1.2 (4K ready), HDMI 1.4a (4K ready. w/ audio), DVI-I (VGA with included adapter), DVI-D (digital only), Quad simultaneous display capable, HDCP compliant, SLI bridge connector (2-way) NVIDIA GPU Boost technology, NVIDIA Adaptive Vertical Sync Technology, NVIDIA SMX shader architecture, NVIDIA PhysX, CUDA technology, NVIDIA 3D Vision Surround support, NVIDIA SLI ready (2-way), ZOTAC Dual Silencer Enhanced Cooling NVIDIA GeForce driver, Microsoft DirectX 11, OpenGL 4.2, Microsoft Windows XP/Vista/7 x86/x64