Please note that if the power supply is a 20PIN port, if it is not a 24PIN port, the socket should be inserted from the circular mark on the circuit board.

Name: ATX Power Supply Transfer Board
Type: HU-M28 ATX-24
Compatible port: ATX (compatible with partial BTX type)
Number of PINs: 24PIN
Switch: Yes
Number of output groups: Four different voltages
Size: 68*63mm
Hole spacing: 62*57mm
Installation hole diameter: 3mm
Weight: 34g

About the 24pin port:
The 24pin port powers the computer motherboard in the host computer. Usually, this port is used together.
Voltage description of each terminal:
-12V to GND, GND is positive, -12V is negative, voltage DC12V
+12V to GND, +12V is positive, GND is negative, voltage DC12V
+12V to -12V, +12V is positive, -12 is negative, voltage DC24V
+5V to GND, +5V is positive, GND is negative, voltage DC5V
+3.3V to GND, +3.3V is positive, GND is negative, voltage DC3.3V
Note it is not recommended to carry high current loads with 12V terminals. They only provide a logic potential to the motherboard, usually with a current of around 300MA