PhysX runs faster and will deliver more realism by running on the GPU. Running PhysX on a mid-to-high-end GeForce GPU will enable 10-20 times more effects and visual fidelity than physics running on a high-end CPU. Portions of PhysX processing actually run on both the CPU and GPU, leveraging the best of both architectures to deliver the best experience to the user. More importantly, PhysX can scale with the GPU hardware inside your PC. Intel and AMD solutions, which utilize the Havok API, are fixed function only and cannot scale.