, has found a solution to running games that have files larger than 4GB from an external Hard Drive. Due to FAT32 limitations users needed to run these games from internal hard drive only. However, it seems that isn’t the only option anymore. Many games utilize a file format known as PSARC (*.psarc) These files ending in .psarc are archive files similar to zip or rar files on PC. By extracting these large archive files and using the smaller files that are inside, users can get stay under the 4GB limit. This method has been tested on Uncharted II, and will only work on games utilizing the psarc file format.
Originally posted by another user
1) download PSARC.zip (linked above)
2) Extract zlib.net.dll and PSARC.exe to any folder.
3) Find any files more than 4Gb for example \PS3_GAME\USRDIR\build\main\pak22.psarc (5 596 444 529 byte)
4) Copy pak22.psarc into zlib.net.dll and PSARC.exe directory.
5) Extract pak22.psarc (just drag-n-drop pak22.psarc to PSARC.exe)
6) Now copy pak22 folder with extracted files to gamefolder \PS3_GAME\USRDIR\build\main\
7) Now you can delete pak22.psarc.

copy PS3_GAME folder with game to your external fat32 usb hdd GAMEZ\Uncharted2\
9) use backup manager to load game, should work fine.