Isolation is essential
The transformer and safety spacing separate hazardous mains from low-voltage computer circuits. This is why PSU internals are not a beginner-serviceable area.
POWER ATLAS
ATX Power Supply
An ATX PSU safely converts mains AC into regulated low-voltage DC while isolating the computer and supervising electrical faults.
Representative form: modern isolated switch-mode ATX PSU. Internal topology varies and dangerous charge can remain after unplugging.
Regulation follows load
Feedback and high-frequency switching continually adjust energy transfer as the computer's current demand changes.
Protection is part of the design
A compliant supply must respond safely to abnormal output conditions; wattage alone does not describe quality.