PSP Guide for RG351 Devices

Last updated: 17JAN2021 (see Changelog for details)

Here’s how to squeeze the best PSP performance out of your RG351P and RG351M.

Table of Contents
First things first
Available emulators
Recommended default settings
Enabling cheats
Loading PSP fonts
Other tips and tricks

Changelog

First things first

When attempting to emulate PSP on the RG351 devices, you must keep in mind that the RK3326 chipset just doesn’t do PSP emulator very well. It simply requires more horsepower to play these games well. I would say that 50% of PSP play comfortably well, and 25% are pretty impressive. But there are many games that just don’t fare well. In general, stick with 2D games, platformers, role-playing games, puzzle games, and racing games.

The PPSSPP emulator caches its data, and so because of that your first few minutes with any game will likely have a bit of lag and stutter. I recommend you continue playing the game to see if conditions improve. This is especially true with racing games; the first lap will have some hiccups, but subsequent laps might be significantly better.

Available emulators

Of the four available firmwares, there are some overlaps. For example, the stock firmware has a standalone version of PPSSPP as well as a Libretro/RetroArch PPSSPP core; the latter is also shared with ArkOS and 351ELEC. In my opinion, the Libretro PPSSPP core is ineffective on the RG351P — I’ve never seen a game that runs better on this core than on any of the other standalone emulators.

The PPSSPP standalone that comes with the stock firmware is pretty good, but has quickly become overshadowed by the v1.10.3 PPSSPP emulator found on ArkOS, 351ELEC, and Batocera. This version has been patched with a “Max FPS” option which allows you to lower the max FPS and improve gameplay performance.

ArkOS is unique in that it also has the Odroid Go Advance version of PPSSPP, commonly referred to as PPSSPPGO. This emulator will sometimes work better than the v1.10.3 version. Here is a quick list of games that appear to do better with PPSSPPGO:

Crisis Core: Final Fantasy 7
Ys SEVEN
Metal Gear Solid: Peace Walker
Metal Gear Solid: Portable Ops

If you’re having trouble deciding which firmware to use, check out my Firmware Comparison Guide.

Recommended default settings

There is no magic formula to make every game work, but here are my recommended settings beyond what is already set by default. In general, I recommend you start with these settings and then adjust things for your favorite game.

Graphics:
Backend: OpenGL
Mode: Buffered Rendering
Frame skipping: 1
Frame skipping type: Number of frames
Auto frameskip: ON
Force Max FPS: 60
Rendering Resolution: Auto (1:1)

System:
Change emulated PSP's CPU clock: Auto

For “Buffered Rendering”, some games will do better with “Skip Buffered Effects” instead, but this is rare.

For “Force Max FPS”, some more graphically-intensive game may benefit from lowering that number. I will typically try 30 FPS, but some have reported success with 20 FPS. Just be aware that the lower the number you choose, the more stilted/jerky the graphics will be.

For “Rendering Resolution”, you may be able to get away with 2:1 for certain low-intensity games, and they will look gorgeous.

For the CPU clock, the default is usually 333, but this may cause compatibility with some games (like Tekken 6). I prefer to set it to zero, which then defaults to “Auto”. Some have reported that 666 also works well, so experiment with your favorite game.

Enabling cheats

Loading cheats onto the PPSSPP emulators is very easy. First, download this package, then unzip it and move the cheat.db file into the following locations. If there is no folder named “CHEATS”, just go ahead and make one.

ArkOS:
EASYROMS/psp/ppsspp/PSP/CHEATS/cheat.db

351ELEC:
GAMES/gamedata/ppsspp/PSP/Cheats/cheat.db

Once you have loaded the cheat.db file, open up a PSP game on your device, then press L2 (ArkOS) or R3 (351ELEC) to bring up the menu. Go to Settings > System > Enable Cheats > ON, then back out to the main PPSSPP menu. You should now see a “Cheats” option. Select that option, then “Import from cheat.db”. When you select this option, it may boot you back to the main menu, which is fine! Go back to the Cheats section and you will see that all the cheats are now loaded.

Loading PSP fonts

Certain games, such as Metal Gear Solid: Peace Walker, require the original PSP system fonts in order to be fully legible. For those game, you will want to add the original fonts (which are copyrights, so I won’t share links). Download the original fonts or extract them from your original PSP, and place all of the unzipped files in the following folder:

ArkOS:
EASYROMS/ppsspp/assets/flash0/font/

351ELEC:
GAMES/gamedata/ppsspp/assets/flash0/font/

Note that in ArkOS, the v1.10.3 PPSSPP (standalone) currently doesn’t pull the fonts correctly, but the PPSSPPGO version does.

Other tips and tricks

Based on community feedback, here are some other tricks you can do to improve performance:

• Some games actually fare better without Buffered Rendering. Games like Monster Hunter Freedom Unite, Lord of Apocalypse, Ultimate Ghosts ‘N Goblins, and Final Fantasy Type-0 appear to have a more consistent FPS by going into Graphics > Mode > Skip Buffer Effects and disabling auto frameskip.
• Go into Tools > Developer Tools and disable everything if they aren’t already. Sometimes there are arbitrary tasks enabled here that can cause unnecessary slowdown.
• Go into Controls > Control Mapping and remove all key mappings for unnecessary functions—particularly things like Speed Toggling, Alternative Speed, and Pause. Just remove any binding (both for physical controller and keyboard) for anything that isn’t used within the actual game, as they have been reported by many to cause slowdown when they have an assigned binding.
• Finally, if you’re really trying to squeeze as much performance as possible out of a game, Going into Sound > Enable Sound > OFF will give you an extra 3-5 FPS (with the obvious expense of no sound in your game).
• GitHub user jserodio has a helpful page where he compiles optimal settings for specific games. If you find optimal settings for a game not listed, just let them know via the Issues tab.

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Changelog

17JAN2021
– published guide
– added other tips and tricks