Rise of The Triad
Not a bad game to be honest they kept the classic feel with modern graphics very well. It uses the unreal tournament engine and the PhysX effects are very demanding on it. I get 60ps constant in most areas, but some areas dip to 45fps on my GTX 770
Also thier is lots of secrets to search for in the maps including secret exits that goe to classic style Rott maps.
i7 2600k @ 4.2Ghz | 16GB Corsair Vengeance DDR3 1333 | 4GB EVGA GTX 770 SC ACX | EVGA Z68 SLI