is this 290x:
Sapphire Radeon R9 280X 3GB GDDR5 DVI-I/DVI-D/HDMI/DP Dual-X OC Version (UEFI) PCI-Express Graphics Card 11221-00-20G
better than this 7950?
Sapphire Radeon HD 7950 3GB DDR5 DVI-I/DVI-D/HDMI/DP with Boost PCI-Express Graphics Card 11196-19-20G
Sapphire Radeon R9 280X 3GB GDDR5 DVI-I/DVI-D/HDMI/DP Dual-X OC Version (UEFI) PCI-Express Graphics Card 11221-00-20G
better than this 7950?
Sapphire Radeon HD 7950 3GB DDR5 DVI-I/DVI-D/HDMI/DP with Boost PCI-Express Graphics Card 11196-19-20G