Small molex power supply? Simple?

Technology
1

I need a power supply that has ONE molex connector (the kind that plug into old hard drives, CD-ROM drives, etc).

Everything I can find is either stupid huge or stupid price - or ATX and provides other things I don’t need. I want something very simple and cheap. Ideas?

I don’t need a ton of power but it does need to provide all the various voltages a Molex connector has - many of the cheap ones designed for USB->PATA/SATA adapters only power one rail.

I am trying to replicate this: TANDBERG DATA 7803-LTO STORAGELOADER LTO4 SCSI | eBay for slightly less than $200 shipped my goodness.

2

12V PSU, 12V → 5V buck converter, and wire it yourself?

3

There’s some Pico PSUs. Stuff like https://smile.amazon.com/RGEEK-Switch-24pin-Supply-Computer/dp/B071P3HMNK or https://smile.amazon.com/RGEEK-24pin-Input-Output-Switch/dp/B07WDG49S8. Just need to put together an appropriate mount, and you’ll probably need to have a switch/button which will short the appropriate pins on the 24 pin header.

4

The shorting header lines is what I am trying to avoid if I can - the idea of making it myself is interesting; I have a 12V powersupply somewhere …

5

“Shorting pins on the 24V header” is literally how you turn an ATX power supply on - short the green line to ground and, ideally, up you go!

If you’ve got a 12V PSU, just get 12V->5V buck converter and wire it up.

Those connectors are just 12V, ground, ground, 5V. As long as the grounds are common, it’ll work fine.

6

Yeah, 12v PSU with a buck to 5v if you have laying around, probably any old that’ll handle 1a should be just fine I expect. Just make sure you put the right voltage on the right pins. You can find those ATX PC peripheral power connector pinout diagram @ pinouts.ru on the left side it shows which is pin 1. Looks like the slanted/keyed sides are up, and pin 1 is the left-most pin.

7

I do have some variable buck converters somewhere, this may be easier than I thought.

I need to dig around - I found the three 12V powersupplies I got at Goodwill but I think I might even have a dual voltage one buried somewhere.

I’m hesitant on the ATX thing because the last time I tried it the wire I’d jammed in there came loose, but that should be fixable if I go that route.

Sadly, I don’t have piles of old computers anymore, and I don’t like the idea of paying for a whole ATX supply when I only need one connector.

8

Just take a finished molex from one of the old PSU and clip it close to the PSU and wire that onto your 12v & 5v supplies.