Handhelds

https://www.rghandhelds.com/handheld-specs

2005 Gamepark gp2x

https://en.wikipedia.org/wiki/GP2X

320×240 3.5 inch

2 Double-A Batteries

B on Joystick->SD Games->Scroll Down to Go-gpu

2005 PSP-1000

https://en.wikipedia.org/wiki/PlayStation_Portable

380X472 4.3 Inch

Internal Battery Custom Charger Plug

B on Wiz CD Card->B on GMenu2x

2009 Gamepark gp2x Wiz

https://en.wikipedia.org/wiki/GP2X_Wiz

320x240 2.8-inch amoled

Internal Battery Custom Charger Plug

A on Interesting Game/ Hit b until you get to micro SD Card.

2009 Dingoo A320

https://en.wikipedia.org/wiki/Dingoo

320 X 240 2.8 Inch

2017 AtGames Sega Genesis Ultimate Portable Game Player

http://atgames.us/Ultimate-Portable-Game-Player-GP3228.htm

320 X 240 2.8 Inch