Custom Firmware 5.50 Prometheus-3 v4 almost when under the radar. And we almost missed this one. It seems Liquidzigong updated 5.50 Prometheus-3 not twice but four times hence the v4. This is the installer by neur0n which includes the official 5.50 and 6.31 update eboots correctly named. The installer extracts the needed prx files from the 6.31 and 5.50 eboots and installs 5.50 Prometheus-3 v4. You need to be running Custom Firmware 5.50 GEN for this to work correctly. This is only for PSP-1000′s to PSP-2000′s that are non TA088v3. Prometheus-3 v4 should let you run pretty much every known PSP game. The 6.31 ones too!
Since all the files are included in this download you don’t need to download official firmware’s 5.50 and 6.31 separately.
Note: Due to the file size this download is located off-site on mediafire.
Prerequisites: You must be running Custom Firmware 5.50 GEN or install Custom Firmware 5.50 GEN-D3
Installation instructions:
1. Just point the self extracting rar archive to the root of your PSP memory stick duo & run it .
2. Then from the XMB Game menu run the Custom Firmware 5.50 Prometheus-3 v4 Installer.