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DC Power from PC-PS

as you might have seen, there are many tutorials and videos
about using a old PC power supply as a 'bench' power supply

here only the basics for a functional volt current feed for testing...
but also i need PS for 5V LED and 12V LED strips, what i buy but without power never tested.


some info about the pins:

remember Tony Stark: "back in hardware mode" Iron Man 2

-1- power cable
-2- power switch
-3- jumper PS ON to GND
and FAN starts ( and not too noisy / why did i exchange it? well my old PC failed too often
and i blamed PS first.. later found that the RAM was bad...

looks good so far,

-4- there is a remark about the need of a minimum LOAD:
10 Ohms / 5W on the +5V output.

-5- and a option to use pin 8 (PG) 'Pwr OK' with a 220 OHM and a LED
to show its operational.

But i go for a LED on each of the 5 outputs

* (1)12V/10A ( 4 yellow wire )
* (2)12V/12A ( 2 yellow wire to 4 pin connector "CPU-Power" )
* 5VSB/2A ( 1 purple wire )
* 5V/20A ( 7 red wires )
* 3V3/20A ( 4 orange wires )

( after each fuse ) so i see THAT fused status too.

* PS-ON ( green ) fix on GND ( PS start command i not need switch as this PS has power switch )

* 14 * GND wires ( black )

* pin 14 -12V ( blue )
* pin 6 PG ( grey )
* pin 20 -5V ( white )

* * resistor 10ohm 10W between 5V and GND as minimum load

little shopping in CNX:

first steel work and worry banana pin isolation, use heat shrink tube.

with color and mounted fuse holder and banana plugs looks good from outside.

with the 10 Ohm 10Watt load on 5V ( and the Start wire fix soldered there to GND too ) and the cable tree separated ( connectors cut )
i see that the info about V1 V2 12V might be wrong... possibly there is only one 12V feed, too late, i made 2 fuse outlet ( planned 10A each ) already.

now even as i have 3 different V outputs want use one ( 3V3, 5V or 12V ) for creating a variable voltage:
by a Step Up Buck converter ( about 5 $ here)

XH-M411 DC-DC 3 - 35V to 5 - 45V / 5A Step Up Converter Boost Power Supply Board,
it might allow to use the 12V to load a 12V battery with max 3A..5A
but also create voltages 5..12V from 3v3 but there the display ( in / out Voltage show [button] ) not work, it needs a min of 5V input!
anyway its great for testing the INA219 ( hi-side shunt meter ..26V 3.2A )
but yes, it is a cheap one... for many applications it is better to have the one with 2 poti, CV & CC mode like here

a day later i see i could have saved some small money but LOTS of work with online shopping
like here

oh no
wire . solder still not finished.
but now i have a reason to finish it, got a good use for it.

while above is a cheap boost converter,
i got today a sweet little thing
FNIRSI DC DC Automatic Boost/Buck Converter
Power Module 0.5-30V 3A 35W / 4A 50W with FAN
Adjustable Regulated power supply



that is different from the documentation,
there is a add 5V fan, but no cooler element??
try to mount the fan anyhow

that is not a UART port i hoped for

power ON