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Power Supply A Guide to 12V PSU

Valantar

Shrink Ray Wielder
Jan 20, 2018
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First step will be to recycle my old setup (i3 6100 + 1050ti) but I may look at the i3-10105F later on. With a power usage of about 50W on full load, that seems pretty manageable. I may go down the same route as you with a 120mm fan hovering above the PSU and 160-XT though. I don't expect any issues with the 160-XT at all though, it has been running for some years without cooling in my previously mentioned setup.
FWIW, that MW PSU tested at 92.95% efficiency at full load in their report, so the worst case scenario for heat output for it is ~12,2W of heat. Even if it "only" matches the 92,5% rating that's still just 13W. Shouldn't need a ton of airflow to dissipate that given that it has a decent surface area exposed to open air.
 
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Curiosity

Too busy figuring out if I can to think if I shoul
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FINALLY wired in my eospower wlp350, for now just GPU but I'll get it hooked up the the barrel connector for the A300 soon.
Working great, I just need to reprint my case and/or get a final case figured out and I'll be in business. Unfortunately I lost several of my files for the design I'd been working on due to being an idiot.

(You can see the 3 prong cable I used to wire in direct to the PSU ziptied to the side of it)
 

msystems

King of Cable Management
Apr 28, 2017
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Since this is probably the best place to leave it, I want to share this xt90 flush mount connector I found on Ali, which should do nicely on enclosure walls.



XT90E-M is designed for 30 amps continuous when paired with pure copper 10ga wire, making this my preferred way to pipe around dc12v.

Anyone deciding how they want to go about running dc into an enclosure might find this useful.

Ive used Amass XT90s for a while now and like their design.
 
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BaK

King of Cable Management
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May 17, 2016
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Hey, I made another 12V build! Would you look at that.
Yes! What a nice build!
Loving the 3D printed AC cover plate!
So you end up not adding an AC filter? I thought this was mandatory to you!

I probably already asked this several times in the forum... but are these tiny 20mm Noctua fans as silent as their bigger brothers?
Since it is there especially for the MW, why not attaching it to the PSU instead of the mobo? I never tried to do that yet with my MW PSUs.

Lol you do not joke with the size of the DC cables!

Is that an Z97I-Plus motherboard we are looking at? The gold Asus logo seems to mean it, I own two, each with a Broadwell on it, best mobo ever!
 
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Valantar

Shrink Ray Wielder
Jan 20, 2018
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Yes! What a nice build!
Loving the 3D printed AC cover plate!
So you end up not adding an AC filter? I thought this was mandatory to you!

I probably already asked this several times in the forum... but are these tiny 20mm Noctua fans as silent as their bigger brothers?
Since it is there especially for the MW, why not attaching it to the PSU instead of the mobo? I never tried to do that yet with my MW PSUs.

Lol you do not joke with the size of the DC cables!

Is that an Z97I-Plus motherboard we are looking at? The gold Asus logo seems to mean it, I own two, each with a Broadwell on it, best mobo ever!
Thank you! It is indeed a Z97I-Plus. I spent ages looking for a good Haswell-compatible motherboard (they are incredibly rare and expensive on Ebay and the like!) and ended up getting a decent offer for that one off a TPU forum member. Good to know you like it so well, as I haven't had much time to explore it. I'm thinking I might try my hand at pushing those generic Dell OEM DDR3-1600 sticks a bit higher, so hopefully the board does that well.

And yes, I'm very happy with that cover plate! As I said in the other threads the measurements aren't perfect and it needed some hand tuning, but it fit, and works very well. As for the AC filter, I wanted to reuse the one I had in the old OptiplRX 570, but since it was screw mount rather than snap-in panel mount it actually couldn't fit there alongside the fan in any orientation. The screw holes just made it too wide. And since I have two of those lying around and didn't want to spend the time or money ordering another one I decided to pass on it. The filtering section in the RPS looks pretty beefy anyhow, and I've probably moderated my stance on this a bit since last time (especially after learning that PSU AC filters mainly filter noise from getting back into the AC line, not the other way around).

This was my first experience with the 40mm Noctuas, and I was honestly shocked at how quiet they were - barely audible at 30-40cm at full speed, which was way quieter than I was expecting. I can imagine the 10mm thick variant is louder, but these 20mm ones are fantastic at least. I've connected it to the motherboard (for now) as I didn't have a suitable connector to hook it to the PSU, and I was thinking I'd try to use the motherboard to control it. Haven't really decided on that yet though. Thankfully this is one of those rare ITX boards with three fan headers, so I'm not running out yet.

As for those DC cables, I kind of wanted to future proof, and I had some 12AWG wire lying around, so why not 😅 Also wanted to see if I could do a better job soldering these than the previous setup now that I have a Pinecil and kinda-sorta feel that I have some understanding of soldering - and the thicker wire was a nice way of testing that. Worked out nicely, and that Pinecil is really amazing for its price. Gury actually uses 14AWG wiring for the inputs to the ArchDaemon, not that my setup will ever need that (can't imagine what CPU+peripherals combination would warrant that!), but I gathered if this will ever come close to supplying 400W including the GPU I might as well go big. I'm actually planning to use the same wiring for a two-wire EPS12V setup in my main PC at some point, just branching it out to thinner wires at the connectors. Now that I know I can solder it easily that seems much less daunting :D
 

BaK

King of Cable Management
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May 17, 2016
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Never heard of that Pinecil soldering iron before, thanks for the info! Cordless but still able to reach 400°C, sounds interesting!
And if you managed to warm your 12AWG wires up enough for proper soldering, then this Pinecil is definitely powerful! ;)
These future proof big wires actually go well with the Amass plug, good choice!

Good to know these tiny Noctuas are that silent!
That makes me want to try them blowing lateraly on a side of a CPU heatsink to save some height. Something like that:

Not enough CFM probably, a push/pull setup maybe?

My Z97I-Plus boards are actually the only 2 motherboards with which I never had a problem with. 🤞
All the others have their little things to bother me!
 

Valantar

Shrink Ray Wielder
Jan 20, 2018
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Never heard of that Pinecil soldering iron before, thanks for the info! Cordless but still able to reach 400°C, sounds interesting!
And if you managed to warm your 12AWG wires up enough for proper soldering, then this Pinecil is definitely powerful! ;)
These future proof big wires actually go well with the Amass plug, good choice!

Good to know these tiny Noctuas are that silent!
That makes me want to try them blowing lateraly on a side of a CPU heatsink to save some height. Something like that:

Not enough CFM probably, a push/pull setup maybe?

My Z97I-Plus boards are actually the only 2 motherboards with which I never had a problem with. 🤞
All the others have their little things to bother me!
Yeah, the Pinecil is great. Heats up quickly, gets really hot, runs off either USB-C or a DC jack (with selectable USB-C voltage if you want to tune it). Up to 60W at 20V USB-C IIRC. I also bought one of their tip kits, though you get those tips easily on Ebay and other places. And the entire thing is open source, moddable and upgradeable, with spare parts and other stuff easily available. It's a really cool piece of kit.

I've seen others try those kinds of fan setups, but rarely with any real success. I think the fans have the pressure needed, but not really the airflow, and for additional airflow you need more fans in parallel - push/pull just increases pressure (and of course increases flow however much overcoming flow resistance through more pressure gets you, but that likely isn't that much). Still, most of the attempts I've seen have had rather lacklustre flow guides, and I think there's a lot to gain there - when you have little airflow, you need to ensure it goes where you want it, after all.
 

CC Ricers

Shrink Ray Wielder
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Nov 1, 2015
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Anyone recommend any tiny UPS boards to use with some low-wattage power sources? Like something that would only need 12V with 2A at the most. Something like this board appears to be what I need, though even that might be a bit too big, believe it or not (it's for a very small portable computer). Otherwise I am not certain how you would fashion a simple system where you daisy chain both the battery with a DC jack, connect that to the load and have the computer use only the DC power source when a wall adapter is plugged in, and then switch to battery when it's disconnected.
 

Valantar

Shrink Ray Wielder
Jan 20, 2018
2,201
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Anyone recommend any tiny UPS boards to use with some low-wattage power sources? Like something that would only need 12V with 2A at the most. Something like this board appears to be what I need, though even that might be a bit too big, believe it or not (it's for a very small portable computer). Otherwise I am not certain how you would fashion a simple system where you daisy chain both the battery with a DC jack, connect that to the load and have the computer use only the DC power source when a wall adapter is plugged in, and then switch to battery when it's disconnected.
Excellent question. The PicoUPS is the smallest I've ever seen, though that AFAIK only works with lead-acid batteries (and would thus likely blow up any LiPo or Li-Ion batteries connected to it 😅. You might try having a chat with @Choidebu to hear what they learned when working on their Roadrunner battery powered S4M project.

Edit: one possible solution - if you're feeling adventurous! - would be to buy a NUC-UPS (4S) or OpenUPS2 (3S), desolder all protruding components on the battery side (including the battery holders) and run soldered-on wires to anything that needs to be connected there. Neither are small, but they do what you need, and if you can work with the protrusions on one side it seems possible to make them at least somewhat slim. There's also the OpenUPS, which is one-sided to begin with and has a smaller board, but doesn't seem to quite have the same potential for slimming down due to its denser design.
 
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GuilleAcoustic

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Anyone recommend any tiny UPS boards to use with some low-wattage power sources? Like something that would only need 12V with 2A at the most. Something like this board appears to be what I need, though even that might be a bit too big, believe it or not (it's for a very small portable computer). Otherwise I am not certain how you would fashion a simple system where you daisy chain both the battery with a DC jack, connect that to the load and have the computer use only the DC power source when a wall adapter is plugged in, and then switch to battery when it's disconnected.
Bicker has a few UPS stuff :


Not cheap though :


 
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Valantar

Shrink Ray Wielder
Jan 20, 2018
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Bicker has a few UPC stuff :


Not cheap though :


Wow, supercapacitor-based UPSes? That's ... probably for some special use cases! No wonder they're expensive. Battery life with something like that would likely be atrocious though. Lucky the cap-less ones support LiFePo4 :)
 

CC Ricers

Shrink Ray Wielder
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Oof... those USP boards are still too big, especially with the supercaps. I just need a 24W max capacity with straight 12v in and out, no conversion needed. I also have my own batter pack already, vinyl wrapped and with its own protection board.

Going to see if using a double throw switch would be good enough to just toggle between battery power and wall power, even if it is more crude.
 
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Valantar

Shrink Ray Wielder
Jan 20, 2018
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Oof... those USP boards are still too big, especially with the supercaps. I just need a 24W max capacity with straight 12v in and out, no conversion needed. I also have my own batter pack already, vinyl wrapped and with its own protection board.

Going to see if using a double throw switch would be good enough to just toggle between battery power and wall power, even if it is more crude.
Have you given up completely on using the Framework's battery connector? Seems like there are others over on their community forums looking to make use of that battery connector. That thread mentions looking at the code for the embedded controller to suss out how it communicates with the battery (or BMS I guess).
 

CC Ricers

Shrink Ray Wielder
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Have you given up completely on using the Framework's battery connector? Seems like there are others over on their community forums looking to make use of that battery connector. That thread mentions looking at the code for the embedded controller to suss out how it communicates with the battery (or BMS I guess).
I'm not sure yet, as I am still waiting on my USB-PD trigger board to arrive to see how that works out with the custom battery pack. Otherwise if that doesn't work as planned I can go back to using the battery connector with a stock Framework battery and plan my case design around it.

With the stock battery, it will have to be a slim sandwich layout where the battery is stacked between the mainboard and screen. I haven't yet seen anyone try this layout with their own mainboard.
 

GuilleAcoustic

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If your willing to DIY, I've found this tutorial to make a 12V 2A one

 

CC Ricers

Shrink Ray Wielder
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@GuilleAcoustic that’s exactly what I’m looking for. Just a simple circuit utilizing diodes with a charge board, just wasn’t sure how you had to place the diodes. Since I’m using a 3S battery pack it could be even simpler, as I can omit the boost converter and substitute the 2S charge module for one that’s meant for 3S.
 

Valantar

Shrink Ray Wielder
Jan 20, 2018
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@GuilleAcoustic that’s exactly what I’m looking for. Just a simple circuit utilizing diodes with a charge board, just wasn’t sure how you had to place the diodes. Since I’m using a 3S battery pack it could be even simpler, as I can omit the boost converter and substitute the 2S charge module for one that’s meant for 3S.
Hmmm. I did a tad of searching to see if there exists a USB-HID battery monitor of some kind. I didn't find anything directly relevant, but this might be of interest to you?


This is way beyond what I'm able to understand, but it seems to provide documentation for USB-based battery charging and monitoring for PC applications using cheap and easily available microcontrollers? Making custom hardware (and firmware for it) like this sounds rather daunting, but possibly doable? And if using a separate charge circuit, not that I know anything at all about programming, but it sounds kinda-sorta doable to make a simple microcontroller-based voltage measurement device that reports this to Windows as a HID-compatible battery readout?

Edit: here's someone using an Arduino to "smartify" their dumb UPS, doing something similar.
 
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