To run Left 4 Dead 2 on high graphics settings your PC will require at least a GeForce GT 230 / Radeon X800 XT with a Core 2 Duo E4600 2.4GHz or Athlon 64 X2 Dual Core 4200+ CPU. System memory required for Left 4 Dead 2 is 2 GB performance memory. To be able to run at all you will need at least 1 GB system memory.