You will need the emulator itself:
Install the emulator and launch it once to create necessary folders.
Open PPSSPP, go to Settings. Do not use "Fast Memory" – it crashes RE4. You will need the emulator itself:
Graphics:
Performance (for highly compressed ISOs): Install the emulator and launch it once to
Controls:
Solution: Many highly compressed versions remove FMV (full-motion video) to save space. Download a version labeled “with cutscenes” or “full content.” Performance (for highly compressed ISOs):
Once you have your highly compressed ISO (let's call it RE4_Ultimate_Compressed.iso), you need to configure the emulator perfectly. The PSP version of RE4 is notoriously heavy on the CPU.
Warning: The internet is full of fake "download now" buttons that lead to adware or surveys. Never download an .exe file if you are looking for a game ISO.
When searching for the file, use specific, safe keywords. A legitimate highly compressed RE4 file for PPSSPP will usually be a .zip, .7z, or .rar archive containing an .iso or .cso file.
Ideal search terms (for informational use):