I have doing this post to report to all about "heavy Games" are playable in RPI3 and help some people to believe and try this if have an Raspberry Pi 3 hardware.
Now, for start :
1) Make sure you have an Heater (dissiper) and a good cooler in your case ( This is extremely important to can run games without temperature issues on RPI
2) Change "overclock" settings to Extrem (1350 or 1375MhZ) and restart your RPI3
3) dowload and use the game configs setting provided here from my tests : https://docs.google.com/spreadsheets/d/1W57PEusE9JZdOFOQ3IUztBrI1PGAeMtWPSVQii809wE/edit#gid=0
Now, run your game and enjoy !!
OBS : Some heavy games for psp are playable most satisfactory in the Raspberry Pi3 in 5.17 version of batocera and now, users can do tests and reports here about this subject :
Games like God of War (very, very heavy graphics for RPI3 ) are playable !! Believe and download config games and discover by yourself
IMPORTANT : RPI is not the best or adequade platform to run PSP heavy games, but are playable in some cases ...no all games are playable, but some games in incredible playable in this new 5.17 Batocera linux for Raspberry pi 3. Give a try !!