Team Fortress 2 Highly Compressed Extra Quality Work -

Provides a 25–35% FPS boost on most systems by streamlining lighting and models.

Maximizing Performance: The Guide to Team Fortress 2 "Highly Compressed" Extra Quality team fortress 2 highly compressed extra quality

By combining legitimate map compression techniques with a high-performance configuration like Mastercomfig, you can achieve a "highly compressed" installation that still delivers "extra quality" gameplay. Provides a 25–35% FPS boost on most systems

Since the 2015 Gunmetal update, Valve has used BSPzip compression for new and updated maps. Community experiments have shown that applying this compression to all maps can reduce the maps folder from 4.23 GB to 2.64 GB—a 38% reduction—without significantly impacting gameplay, though it may slightly increase initial loading times. Standard HUD elements are rendered inefficiently

This is widely considered the gold standard for TF2 performance. It optimizes both graphics and networking.

Standard HUD elements are rendered inefficiently. Using a custom, lightweight HUD like LightHUD or m0rehud can gain you an extra 2–3% in performance.