What do atX and AT chassis mean? What do atX and AT stand for?

ATX/AT chassis is mainly used for power supply.

AT and ATX

* * * There are four outputs (+5V, -5V,+12V,-12V), and one P.G. signal is provided to the motherboard. The volume of AT power supply is150 mm×140 mm× 86 mm.

When the computer is turned on and off, if AT power supply is used, the power supply will not be turned off until the computer power switch is turned off.

Extended data:

ATX power supply adds "+3.3V, +5Sb and PS-on" three outputs. Among them, +3.3V output is mainly used by CPU, while +5Sb and PS-On output reflect the characteristics of ATX power supply. ?

The main feature of ATX power supply is that it does not use the traditional mains switch to control whether the power supply works or not, but uses the combination of "+5Sb and PS-ON" to switch the power supply. As long as the signal level of "PS-ON" is controlled, the power supply can be turned on and off. Turn on the power supply when PS-on is less than 1V, and turn off the power supply when it is greater than 4.5V ..