Gigabyte GeForce GTX 550 Ti 1GB GDDR5 PCI Express 2.0 DVI-I/HDMI/D-Sub SLI Ready Graphics Card GV-N550D5-1GI Gigabyte Ultra Durable 2 Components - Ultra Cooling Low RDS(on) MOSFET Design - Low Power Loss Ferrite Core Chokes - Longer Life All-Solid Capacitor Design Gigabyte Custom-Designed 100mm Fansink for maximum cooling efficiency and whisper silent operation. Gold plated HDMI for optimum signal transfer between connections Features DVI-I/HDMI/D-Sub (VGA) outputs with HDCP protection Core Clock: 900 MHz - Memory Clock: 4100 MHz Supports NVIDIA SLI/3D Vision/CUDA/PhysX Technology Minimum recommended Power Supply Unit 400W with one 6-pin external power connector.