
Here’s another great how to on converting an ATX power supply to a lab power supply, Abizar writes “Computer power supplies are US$15 but lab power supplies are US$100+. By converting the cheap (free) ATX power supplies that can be found in any discarded computer you can get a phenomenal lab power supply with huge current outputs, short circuit protection, and very tight voltage regulation.” Link. See previous.
10 thoughts on “HOW TO – Convert a computer ATX power supply to a lab power supply…”
Comments are closed.
What’s the reason for connecting the 10ohm power resistor between +5 and Ground?
It will not turn on otherwise (well some atx powers suplies won’t), Alot of switching power supplies need some load on that rail to turn on. We built a few of these before, but we never really needed the loads on that 5 rail to turn them on. Its not a bad idea anyways, since the cheapo circuitry may burnout premeturely if its not loaded correctly… but have fun with your $20 powersupply!
nice to see this version shows/tells how to mix and match the +- 5V and +-12V (and some do it with the +- 3V) for interesting (useful) voltages like 7V and 24V, and 10V.
Why is the power resistor > 10 W ? If ten ohms are put across 5 volts, the power (V^2/R) is 2.5 Watts.
I wonder if I put a permanent load on the standby +5V of an ATX power supply (purple wire), do I need the 10ohm load resistor? The load is an electronic circuit that I guess will not draw more than 50-100 mA.