Convert a PC PS to a Bench Power Supply

RE: Convert a PC PS to a Bench Power Supply

kmikemoo — Mon, 25 Dec 2023 05:00:34 GMT

Thank you for doing the [mention:193ac2434c814a24b46635a2210baec1:e9ed411860ed4f2ba0265705b8793d05] annual recap. While it's been 3 years, I'm finally getting back to this one. [emoticon:1435ff2429184e17bc948e4f19178e1e]

RE: Convert a PC PS to a Bench Power Supply

jmotec — Thu, 14 Jan 2021 13:42:44 GMT

Very cool! [View:/resized-image/__size/16x16/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-abf24274-79d5-469b-ae1a-acb190baefda/contentimage_5F00_930.png:16:16]

RE: Convert a PC PS to a Bench Power Supply

dixonselvan — Thu, 24 Dec 2020 06:54:50 GMT

Good job [mention:193ac2434c814a24b46635a2210baec1:e9ed411860ed4f2ba0265705b8793d05] I have been meaning to build a bench power supply. You have made it look so easy and neat. The 3D printed case looks great. Thanks for this project build blog. Hope I'll build one for myself soon.

Seasons greetings and advance Merry Christmas wishes to you!

RE: Convert a PC PS to a Bench Power Supply

ajcc — Thu, 10 Dec 2020 23:36:01 GMT

It's a really neat build and I especially like the handle on top. You're continuing to impress with what you manage to make with the 3D printer! It's a shame your PSU didn't have a -5 Volt rail, although it's easy to live without. I'm curious if you figured out why it didn't power down when you were no longer grounding the /PS_ON pin?

I really liked the idea and got some ideas for how I'd improve it (for my use). First I was curious if the +5 Volt standby voltage (5VSB) could deliver enough power so that it could be used to power a USB-device. On page 21 in Version 2.2 of Intel's ATX Specification from 2004 it states that: "It is recommended that the 5VSB line be capable of delivering 2 A.", that's a recommendation so manufactures might have a different rating for that rail (or comply to a different version of the ATX specifications). Another thing I'd consider adding would be an LED for the PWR_OK signal, which is put out by the PSU when the rails are Okay and it's ready to deliver power.

It's a great little PSU and I want one too! [View:/resized-image/__size/16x16/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-abf24274-79d5-469b-ae1a-acb190baefda/contentimage_5F00_1.png:16:16]

RE: Convert a PC PS to a Bench Power Supply

balearicdynamics — Mon, 26 Oct 2020 08:21:06 GMT

Hi Doug, this project sounds really nice. I am a great user of the ATX power supply when in a project several. power supplies are needed. I struggle if it is also possible – maybe to the highest power out – to add a digital regulator to change the power range(s), just like in a traditional bench power supply.

Enrico

RE: Convert a PC PS to a Bench Power Supply

jw0752 — Sun, 25 Oct 2020 14:18:39 GMT

Hi Doug,

Beautiful build. One of the first power supplies I put together was a PC power supply conversion. Unfortunately it is very crude and lacks the nice planing that went into yours. Thanks for sharing your ideas and builds.

If we ever get a chance to put together that meeting in Toronto it will be a swap meet as well as I too was going to bring a bunch of stuff to give or trade away. I also have the looming problem of what to eventually do with all my cool treasures. I have always hoped that one of the grand kids would take an interest but so far it hasn't happened. There are very few people that would understand its value or see it as anything but a pile of junk. Sad.

John

RE: Convert a PC PS to a Bench Power Supply

Gough Lui — Sat, 24 Oct 2020 11:06:23 GMT

Something to be wary of is that if you don't have any over-current protection, the ATX spec allows up to ~20A to be drawn before tripping a short circuit protection which is enough current to make thinner wires get toasty real quick. More than that is the fact that more modern power supplies are even more lax about this - originally dividing up the beefy 12V rail into multiple rails that fit under the limit, but depending on how you wire the supply, it can be possible to short both rails together and thus exceed that 20A "limit". Later "gamer" style supplies eschewed the multi-rail design as that would occasionally cause heavy-load devices to trip their OCP limits, instead going for a single beefy 12V rail which might have 60A available (sometimes even more).

While the power of the quality PSUs should be top notch, the lack of a current limit is a big concern for this reason. The lower-quality power supplies (e.g. no-brands from China) and older supplies which have served their time may not have such nice ripple and noise specs as well due to poor/aged capacitors. I also wouldn't count on the output to be isolated from ground (often, it is not), so it's not a wise idea to series units together for other voltages. It's a good fall-back for common voltages assuming you have nothing else, but I wouldn't be too enthusiastic about it having done a similar thing with AT supplies and fighting with minimum load, audible noise (at times) and cross-load behaviour (e.g. some supplies will have out-of-spec voltages if the loading on the rails doesn't approximate a PC in some way).

- Gough

RE: Convert a PC PS to a Bench Power Supply

apreed — Fri, 23 Oct 2020 19:29:50 GMT

That printed case is really nice!

Can I ask what printer you used?

RE: Convert a PC PS to a Bench Power Supply

maxpowerr — Fri, 23 Oct 2020 19:13:15 GMT

Nice work, nicely done I like it. Did you make printed circuit boards chemically? They look very neat.

RE: Convert a PC PS to a Bench Power Supply

colporteur — Tue, 20 Oct 2020 16:48:21 GMT

You indicated you are building a few. Any spares to ship to Canada?

RE: Convert a PC PS to a Bench Power Supply

three-phase — Mon, 19 Oct 2020 20:02:16 GMT

A great project, well thought out design and implementation. Thanks for sharing.

Kind regards.

RE: Convert a PC PS to a Bench Power Supply

surbhika — Sun, 18 Oct 2020 20:14:29 GMT

I've an old spare CPU too which has been jobless for a long time... I might as well try this soon.. good work Douglas.

RE: Convert a PC PS to a Bench Power Supply

genebren — Sun, 18 Oct 2020 19:11:56 GMT

Excellent build. Once again, I am blown away by the quality of your builds and the amazing pieces that you are able to print.

Well done!

RE: Convert a PC PS to a Bench Power Supply

DAB — Sun, 18 Oct 2020 17:56:22 GMT

Great build Douglas.

DAB