Garry's Mod is a long-running sandbox built on the Source engine where players spawn and manipulate props, vehicles, and NPCs from Valve games to create contraptions, films, or participate in community-run game modes. Most players spend their time on multiplayer servers running DarkRP for roleplay, Trouble in Terrorist Town for deduction and betrayal, Prop Hunt for hiding as objects, or skill-based maps like Bunny Hop and Deathrun. The experience is heavily shaped by thousands of Steam Workshop addons that add custom models, weapons, maps, and scripts. In high-FPS scenarios, the goal shifts from visual fidelity to responsiveness and smoothness. Competitive or movement-focused modes reward low input lag and consistent frame delivery so that precise jumps, quick turns, and instant reactions feel reliable. Performance load in these situations comes from high prop and NPC counts, real-time physics calculations, entity networking across players, and Lua script execution on crowded servers. The legacy Source engine still favors single-thread performance even after its 64-bit update added better multicore support. Players often encounter stuttering when spawning complex contraptions or joining mod-heavy servers, long loading times for Workshop content, and frame-time instability that makes physics feel mushy. Common misunderstandings include over-focusing on the GPU when the real bottlenecks are usually CPU clock speed and memory bandwidth for handling the constant stream of scripted events and physics objects. Before choosing parts for a high-FPS Garry's Mod PC, understand that the game scales more with how quickly one core can process the simulation loop than with raw multi-core counts or high-end graphics horsepower. Ample fast RAM and quick storage also reduce hitches while loading large addon collections and maps.