Computer Power Supply

Replacement: None. We do not have a direct replacement for this, it has been discontinued. This page is for reference only.

This is a very standard 350W ATX power supply. It’s got a 20+4 main power connector, an SATA power connector and four peripheral connectors. This power supply also has overvoltage and overload protection.

The input voltage is 115/230 VAC (@50/60Hz), and a standard PC power cable is included.

Why is SparkFun carrying a computer power supply? Because it works great with our ATX Connector Breakout Board! Pair the two together and you have a cheap, but very useful bench power supply, which can source 3.3V, 5V, and ±12V.

  • Connectors:
    • Main connector (20+4Pin)
    • 12V (P4)
    • peripheral
    • SATA
    • Floppy
  • Input current: 12A @ 115V, 6A @ 230V
  • Output:
    • +3.3V@20A
    • +5V@30A
    • +12V@15A
    • -5V@0.5A
    • -12V@1A
    • +5VSB@2A
  • Low Ripple & Noise
  • Overvoltage protection
  • Overload protection
  • Short circuit protection on all outputs
  • Reset table power shut down
  • Complies with FCC part 15 subpart J Class B at 115VAC
  • 100% burn-in under high ambient temperature (50°C)
  • Vacuum-impregnated transformer
  • UL, TUV, CB & CE approved
  • 5.75 x 5.5 x 3.25" (WxLxH)

Customer Comments

  • Would the 12 volt output for this power supply work using a easy driver powering a Nema 17 Stepper motor?

  • “Short circuit protection on all outputs"
    "Overvoltage protection"
    "Overload protection"
    The protection is blowing up the transistors inside? What outputs are protected? My faulty PCB with a ATX power connector wired wrongly caused this PSU to get on fire… cool :S :S
    I’ve buyed this one because of the protection, but it seams to be just another cheap PSU :‘(
    RIP power supply :’(

  • overload protection huh? well somehow i killed it whilst copper plating. also when i opened it up to look for fried chips, i noticed the fan was unplugged. that would explain why the fan never turned on!

  • I modded a computer PSU to power my Reprap and for breadboard power. I highly recommend doing so. I would also recommend buying from Sparkfun, I bought a similar unit from a local pc supply store for about twice as much.
    FYI, I used this site as a guide, it’s less of a tutorial, but has lots of good info. http://web2.murraystate.edu/andy.batts/ps/powersupply.htm

  • What size screw fits into the 4 holes in the back? Is it 6-32?

    • I don’t know what the actual threading is, but it should work with the hex+Philips screws you can find by the bucketload on, in, or around just about any computer or computer supply store

  • I’ve actually ran several atx power supplies for days with now modifications. I grounded the PS-ON to enable the supply and had an old pc case fan running off the +5V bus

  • as MF said, this is an ATX PSU, and it may be that without a load across +5v/Gnd, it will not want to turn on. In the link, it is mentioned that not all units require this Built-in load. Suggested method is to include a 10ohm heavy-duty ceramic resistor, attached to the frame to sink heat. (suggested reading for such a task: http://www.instructables.com/id/ATX–%3E-Lab-Bench-Power-Supply-Conversion/ )

    • I am in the process of modifying a power supply that my high school’s tech department gave me using the same tutorial. Haven’t turned it on yet, but I’m almost there.

  • If this PSU hasn’t been modified you’ll have to ground the PS_ON pin (pin no. 16, green cable) so it turns on the power on all the output rails. If you don’t do so, only the +5VSB pin will have power.

Customer Reviews

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