This week Hitman was updated, the second episode based in the Medeterranean setting of Sapienza. After the update you'll notice that radeon card work great with the latest AMD Radeon Software Crimson 16.4.2 driver. The results for GeForce cards (GeForce 364.72 WHQL driver) are pretty dramatic, even lower than DX11.
Read the updated content at page 7 of the updated article.