Cities Skylines 2: Best GraphicSettings.coc for Large Cities

Cities: Skylines 2 uses a modern rendering pipeline that utilizes “Virtual Texturing” and “Global Illumination.” The primary bottleneck in large cities is the “instance count” of high-poly assets like pedestrians and vehicles. Modifying the GraphicSettings.coc (the game’s specific configuration format) allows you to disable the most taxing sub-systems, such as Depth of Field and Volumetric Clouds, which do not scale well with high density. This guide provides a “Mega-City Stability” configuration designed to keep your FPS stable during high-speed simulation.

Hardware Compatibility & Expectations

• VRAM Intensive: High-density cities require significant VRAM for virtual textures. These tweaks help optimize texture streaming to prevent “stutters.”
• CPU Synergy: By lowering the graphical complexity of individual “Cims” (citizens), you free up GPU resources to handle the massive draw calls sent by the CPU.
• Resolution Scaling: Essential for 4K users. Using these settings alongside DLSS or FSR is the only way to play large cities smoothly.

Backup and Preparation

The .coc file is sensitive to manual edits. Ensure you follow these steps:

1. Completely exit Cities: Skylines 2.
2. Navigate to the AppData folder (path below).
3. Right-click GraphicSettings.coc, select Copy, and save a backup copy on your desktop.
4. Use Notepad or Notepad++ to edit the file.

File Location

The configuration file is located in the local Colossal Order directory: %LocalAppData%\Low\Colossal Order\Cities Skylines II\GraphicSettings.coc

Best Config Settings

Open the file and search for the following keys. Update the values to match this high-performance stability preset:

{
    "m_DepthOfField": { "m_Enabled": false },
    "m_Volumetrics": { "m_Enabled": false },
    "m_MotionBlur": { "m_Enabled": false },
    "m_Shadows": {
        "m_ShadowQuality": 1,
        "m_MaxShadowDistance": 500
    },
    "m_LevelOfDetail": {
        "m_LodCrossFade": false,
        "m_MaxLod": 1
    },
    "m_VirtualTexturing": { "m_MaxResidentMips": 512 }
}

Key Parameters Explained

Parameter	Recommended Value	Impact
m_DepthOfField	false	Disables the “blur” effect; massive FPS gain when zoomed out.
m_Volumetrics	false	Disables complex 3D clouds and fog, which are extremely heavy on the GPU.
m_MaxShadowDistance	500	Prevents the game from calculating shadows for buildings far beyond your view.
m_MaxLod	1	Forces the game to use simpler models for distant objects earlier.
m_VirtualTexturing	512	Optimizes the “Mip” count to save VRAM on high-density maps.

In-Game Settings vs. Config

To ensure these tweaks work effectively, match them with these in-game “Graphics” selections:

• Dynamic Resolution Scale: Set to Constant. This prevents the game from constantly changing sharpness, which can be jarring in large cities.
• Global Illumination: Set to Low. This reduces the light “bounce” calculations between buildings.
• Animation Quality: Set to Low. This is the most important setting for large cities, as it simplifies citizen movement logic.

Troubleshooting & Common Fixes

• Characters Look “Ghostly”: This is often a result of TAA (Temporal Anti-Aliasing) in large cities. If it persists, try enabling DLSS (Quality) to replace the native AA.
• Texture Flickering: If your virtual textures flicker, increase the m_MaxResidentMips in the config to 1024, provided you have more than 8GB of VRAM.
• Simulation Speed vs. FPS: If your FPS is high but the game “slows down” (cars moving in slow motion), your CPU is the bottleneck. Lowering graphics won’t fix this; you may need to reduce the number of public transport lines.

Frequently Asked Questions (FAQ)

Conclusion and Expected Results

By manually refining your GraphicSettings.coc, you are prioritizing the simulation’s health over unnecessary cinematic effects. You can expect vastly improved frame stability during zooms, snappier UI performance, and reduced GPU temperatures during long play sessions. Your metropolis is now ready for the next million citizens.