PSP 352 M33 → 6.60 PRO-C or 6.61 PRO Upgrade — Compact Review Summary
The PSP 3.52 M33 custom firmware era was beloved for its stability and homebrew support; upgrading to 6.60 PRO-C / 6.61 PRO modernizes compatibility with newer games and plugins while retaining homebrew functionality. Expect broader plugin support, improved ISO/CSO loaders, and better compatibility with newer PSP titles and some PS1 classics.
What changes and benefits
Kernel features: Later 6.60/6.61 PRO variants provide more complete kernel module support, enabling more plugins (cheats, custom VSH themes, network tools). Plugin ecosystem: Many modern plugins and loaders target 6.60/6.61, so you’ll get access to up-to-date ISO mounting, music/video decoders, and utility patches. Game compatibility: Better compatibility with newer UMD/ISO releases and some homebrew that expect more recent syscall implementations. Stability: Generally stable if you follow proper installation steps and use well‑tested builds; occasional plugin conflicts possible. PSP Go / Slim compatibility: Later CFWs improve support for model quirks compared with older M33 builds. psp 352 m33 upgrade to 660 portable
Potential downsides
Installation risk: Flashing custom firmware always carries risk (bricking) if steps aren’t followed precisely or power is lost. Plugin/patch regressions: Some older M33-specific plugins or tweaks may need updates or replacements. Official firmware gaps: Some newer features added in later official Sony firmware iterations may still be missing; functionality depends on the specific PRO build chosen. Legal/ethical: Running copyrighted ISOs or bypassing DRM is illegal in many jurisdictions; use homebrew and legally owned content only.
Recommended build (practical)
Choose 6.60 PRO-C or 6.61 PRO depending on target compatibility. 6.60 PRO-C has the largest community support historically; 6.61 PRO can be selected for edge fixes if available for your model. Use a model-appropriate installer (PSP Fat, Slim, or Go). Prefer permanent installs only for well-supported hardware; otherwise use the reversible PRO Downgrader/PRO installer as needed.
Installation checklist (concise)
Backup PSP: EBOOT.BIN, SEPL, and ms0:/PSP/GAME folders, and important saves. Charge battery to >80% and use AC power if possible. Download the correct PRO CFW package for your PSP model and a reputable guide (model-specific). Place installer on ms0:/PSP/GAME/ and run from Games → Memory Stick. Follow on-screen prompts; install; reboot into CFW and test VSH and Recovery Menu. Install/update necessary plugins (e.g., PROLoad, popsloader for PS1, CXMB for themes) and configure ms0:/seplugins/ with correct lines. Test a known-good homebrew and one ISO loader to verify stability. PSP 352 M33 → 6
Suggested plugin/utility list
PROLoad or 6.60+ compatible ISO loader (for ISOs/CSOs) CXMB (custom theme loader) popsloader (PS1 compatibility) FastRecovery (if using temporary installs) / HOMEBREW ENABLER (model dependent) Game Tweak plugins: CPU speed control, NoDRM tools (legal caveat), screenshot utilities