The most common power supply connectors for motherboards will be either a 20 or 24 pin connector. Older unit used less pins like the ATX but the cure standard is the 20 or 24 pin main connector.
Many/most motherboards have a separate power connector for the CPU. Check your motherboard's installation instructions to locate the CPU power connector. Then connect the matching power supply cable to the CPU power connector on the motherboard.
To provide extra power for more powerful motherboards.
If it as a 20 or 24 pin connector and a 4 pin connector then it is a ATX power supply.
The atx 12 connector is one of the motherboard power connectors and used for 12 volt power connect for cpu voltage regulator.
24 pin connector is required to supply power to the motherboard.
Power supply is dictated by your motherboard, simply get the power supply which matches the motherboards pin configuration.
systems that have the standard ATX motherboards.
power supply
The main power connector 20-24pin. One for the CPU 4-8 pin. PCI express 4 pin. It's depend on what type of motherboard do you have. But commonly, new motherboards uses 2 power cord P8 and P9.
15 & 16 and 16 & 17
An ATX power supply unit delivers power in three voltages: 3.3 volts, 5 volts, and 12 volts. The 3.3 volt pins are used only in the motherboard connector. Older, AT power supplies and motherboards used only 5 volt and 12 volt pins in the motherboard connection.
The SATA connector on a power supply is to supply power to SATA-based hard drives. It is not to be confused with the ATX plug that is to give extra power to the CPU, nor the PCI-e power connectors that give extra power to certain video cards. It is unexpected to find a SATA style connector on the motherboard.