AMD Benchmarks Show Radeon R9 290X Outgunning Nvidia GeForce GTX 780 at 4K Resolution

BioShock Infinite (3840x2160, Ultra Settings)

AMD Radeon R9 290X "Quiet Mode" average frame rate: 44.25
Nvidia GeForce GTX 780 average frame rate: 37.67

Tomb Raider (3840x2160, Normal Preset w/ TressFX On)

AMD Radeon R9 290X "Quiet Mode" average frame rate: 40.2
Nvidia GeForce GTX 780 average frame rate: 34.5