Sapphire   Radeon HD 7790 OC 1GB DDR5 DL-DVI-I/DL-DVI-D/HDMI/DP PCI-Express Graphics Card  11210-01-20G PCI-E 3.0 x16 2 Slot dual fan 1GB memory; 128-bit GDDR5 memory interface 1075 MHz core speed 6400 MHz effective memory speed