PC Power Supply Modification(perfect version)

[makuang]

perfect way:
1. same as simple way, enable the PS. No idea about what i am talking, please see here


2. check the circuit. there should be a PWM controll IC on the PCB board, TL494 is quite common in PC PS. normally pin 1 of the IC is the reference point.

[makuang]

this is one of a ATX PC PS circuit diagram. you may find the reference on pin 1 of TL494.
R26 and R50 is the voltage devider. now all the story will be around these two resistors.

[makuang]

these two resistors in my PC PS are configered in the way below

[makuang]

Find out the reference connection to +5V, cut it, and jump it to 12V.
change the value of the one connect to ground as shown below, or use a 10K multi-turn pre-set resistor.

[makuang]

this is the pic after i done the modification

[makuang]

While you are doing this,, must be very careful.. 230V on the board when you connect to AC!!!

if you are not confident enough please DO NOT do this!!!!

Doing this project under your own risk!!!!

[makuang]

3. do some necessary finishing to become a prefect RC power supply

like the one in this thread:
PC Power Supply Modification



Have Fun!!

Ma Kuang