Which One Should I Get

[Aviad AB]

I want to buy a new graphics card which one should i get the MSI GTX760 Gaming 2GB GDDR5 or Sapphire Radeon R9 280 DUAL-X BOOST OC 3GB GDDR5?
my rig;
i3 540
4GB ram
MOBO: GA-H55M-D2H

 

[Embra]

Did complete specs.

R9 280 is faster in most games.