Just picked up Tomb Raider (2013) for PC and I thought I’d post the settings I’m using for others to try.  I don’t have the best card around so I attempted to dial in something the card was able to do while maintaining 30fps.  I’m running the latest Nvidia drivers as of 3/5/2013 and Nvidia has already stated that they were caught off guard so hopefully the framerate will improve with updated drivers and/or settings can be increased.

2GB 550 Ti Tomb Raider settings

 resolution: 1920x1080
 refresh: 60hz
 v-sync: double buffer
 fullscreen: on
 exclusive full: on
 display: 1
 monitor aspect auto
 quality custom,

 texture quality: ultra
 texture filter: anisotropic 4x
 hair quality: normal
 anti-aliasing: fxaa
 shadows: normal
 shadow resolution: high
 level of detail high: high
 reflections: high
 depth of field: normal
 ssao: normal
 post processing: on
 tessellation: off
 high precision: on

min: 30, max: 44.0, avg 33.2