CSO files use 9 levels of compression. Finding the "Full" or "Perfect" balance is key: Performance Recommendation Fast loading Best for high-action games (GTA, God of War). Great all-rounder for RPGs and Puzzles. Potential Lag May cause stuttering in FMVs or long load times. 🔍 Where to Find "Full" Archives

A compressed version of the ISO. It drastically reduces file size—often by 30% to 60%—but requires the PSP processor to decompress data on the fly during gameplay. Why Use a Full CSO Archive?

Tip: Level 9 offers the smallest file size, but it can cause audio stuttering or lagging frames in high-performance games like God of War: Ghost of Sparta or Midnight Club 3. How to Build Your Own CSO PSP Archive

For PSP users, upgrading to a higher capacity Memory Stick Pro Duo can provide more room for your games and applications.

Download a command-line tool like maxcso or a GUI tool like PSP ISO Compressor .

Building a full archive in CSO format offers three distinct advantages:

A file is a sector-based compression format specifically designed for PlayStation Portable game dumps.