Sapphire ATI Radeon HD 4670 1GB GDDR3 DVI HDMI D-SUB PCI-Express 2.0 x16 Graphics Video Card 288-DE101-540SA. Sapphire Part Number: 288-DE101-540SA ATI Model Number: Radeon HD 4670 Compatible Part Numbers: 11138-31 Specifications: Interface Type: PCI Express 2.0 x16 Graphics Processor Manufacturer: ATI Graphics Processor: ATI Radeon HD 4670 Clock Speed: 750 MHz RAMDAC Clock Speed: 400 Hz Max Monitors Supported: 2 Max External Resolution: 2560 x 1600 Size 1 GB Effective Clock Speed 800 Hz Technology GDDR3 SDRAM API Supported: DirectX 10.1 OpenGL 2.