Visit the RetroArch Platforms Page and scroll down to the PlayStation 3 section.
For the latest "Community Edition" with optimized cores, check the PSX-Place forums . Installation Guide How To Install RetroArch On Your PS3 retroarch.ps3.cex.ps3.pkg download
This is only for consoles converted to developer firmware. Where to Download Visit the RetroArch Platforms Page and scroll down
This version is for standard retail PS3s running PS3HEN or a CEX-based Custom Firmware (CFW) like Evilnat. retroarch.ps3.cex.ps3.pkg download