Identify the ATX power connector in the image given below.

Answer:

Explanation:

ATX main power connector: This connector is used in ATX, SFX, and in all ATX oriented form factor
power supplies. It is a 20-pin connector with a square hole for pin 1 and round holes for the other 19 pins.

Reference: “http://www.hardwarebook.net/connector/power/atxpower.html”