are ATX to ATX 12VO adapters possible?

[17030644]

We know ATX 12VO is sort of becoming a thing, but,

 

is it possible to make use of today's PSUs with an ATX 12VO motherboard? I mean, less e-waste and people don't have to spend an extra to upgrade the PSU

 

from my understanding, voltage regulation and ripple requirements haven't changed, only ATX 12VO PSUs no longer output 3.3 and 5V 

 

with that being said, there's already a lot of components are fed with 12V anyway, it's just a matter of adapting EPS and/or PCIe +12V and GND wires to the main 10-pin connector.

 

But I worry about the 5VSB, PS_ON and PWR_OK pins, ATX12VO has 12VSB for that IIRC

 

is it possible to use step-up converters to go from 5VSB to 12VSB and make today's PSUs fully compatible with ATX 12VO mobos?

 

Are there other requirements that aren't met by regular ATX PSUs?

 

 

[Chris Pratt]

Why would you want to? The entire point of 12VO is the PSU. Even if you could adapt it to an ATX power supply, you're cancelling out all the benefits. Just get a regular ATX board.

[Juular]

I guess just making the PSU to be always powered and using a 12V rail as 12VSB is an option. Would be even as simple as a passive adapter with the PS-ON always shorted or having a switch there. We would probably see these things eventually when 12VO PSUs would become a thing.

The harder part would be adapting a 12VO PSU for an ATX motherboard, for whatever usecase that might be, it would require a board with DC-DC converters, converting 12V to 5V and 3.3V and 5VSB to 12VSB. Kinda like that thingy i don't remember the name of, that plugs into motherboard 24-pin slot and in PSU's 24-pin on the other end, routing only 12V and 5VSB IIRC to save space in extremely cramped SFF builds.

[electropical]

1 hour ago, 17030644 said:

We know ATX 12VO is sort of becoming a thing, but,

 

is it possible to make use of today's PSUs with an ATX 12VO motherboard?

Yes, definitely.
Corsair already sells adapters to do it :
https://www.corsair.com/us/en/Categories/Products/Accessories-%7C-Parts/PC-Components/Power-Supplies/ATX12VO-Adapter-Cable/p/CP-8920272

[Spotty]

6 hours ago, Juular said:

Kinda like that thingy i don't remember the name of, that plugs into motherboard 24-pin slot and in PSU's 24-pin on the other end, routing only 12V and 5VSB IIRC to save space in extremely cramped SFF builds.

Pico PSU? You don't need 5VSB in that case since it's done on the board, it's usually just powered by a single 12V input. I guess you could use a Pico PSU board to power an ATX board from an ATX12VO PSU with minimal soldering. 12V for power and passthrough the pwr_ok and ps_on to the ATX12VO PSU. As ATX12VO becomes widely adopted you will probably see people on eBay selling basically the same thing (just a DC-DC voltage regulator with a 24pin motherboard connector on it) with the 10pin connector to make it simple to use. Can even go the other way from an ATX PSU to ATX12VO motherboard with just a 5V to 12V boost converter for standby.

[Spotty]

6 hours ago, electropical said:

Yes, definitely.
Corsair already sells adapters to do it :
https://www.corsair.com/us/en/Categories/Products/Accessories-|-Parts/PC-Components/Power-Supplies/ATX12VO-Adapter-Cable/p/CP-8920272

Interesting, I didn't realise Corsair was selling that. Judging by the cable looking like a snake just swallowed a rabbit they fit the DC-DC converters in to the cable sleeving? Inb4 everyone complains about how stiff the cable is in the middle. Hopefully no-one breaks it trying to force the side panel closed on it or while bending it in some weird angle to cable manage it.

[Juular]

6 hours ago, Spotty said:

Pico PSU?

This thing :

https://smallformfactor.net/forum/threads/how-it-works-and-how-to-install：g-uniq-u0-experience-suite.9734/

[Spotty]

1 hour ago, Juular said:

This thing :

 

https://smallformfactor.net/forum/threads/how-it-works-and-how-to-install：g-uniq-u0-experience-suite.9734/

Image doesn't load btw, but yeah the little ATX connector is a pico PSU. You just need the ATX connector part.

 

https://www.onlogic.com/picopsu-160/

 

Something like that for example. It takes +12V (from an external power supply) and converts it to the needed 3.3V, 5V, 5VSB, -12V. You wouldn't even need the molex/SATA/CPU connector that comes off this since that would be provided by the motherboard for SATA/Molex and you can use the CPU/PCIe connectors from the PSU. You would just need to solder +12V and ground wires to it from the PSU.

[17030644]

On 6/21/2021 at 10:56 AM, Chris Pratt said:

Why would you want to? The entire point of 12VO is the PSU. 

nope, the point is not to have to replace completely working PSUs whenever ATX 12VO comes to DIY, that's why I asked

[17030644]

On 6/21/2021 at 11:39 AM, Juular said:

I guess just making the PSU to be always powered and using a 12V rail as 12VSB is an option. Would be even as simple as a passive adapter with the PS-ON always shorted or having a switch there.We would probably see these things eventually when 12VO PSUs would become a thing.

 

 

On 6/21/2021 at 6:47 PM, Spotty said:

 Can even go the other way from an ATX PSU to ATX12VO motherboard with just a 5V to 12V boost converter for standby.

What would be best? 12VB generated from 12V or 12VB using a boost converter fed with 5VSB?

 

Considering that the 5VSB rail is only rated at 2.5A in some PSUs

[Chris Pratt]

56 minutes ago, 17030644 said:

nope, the point is not to have to replace completely working PSUs whenever ATX 12VO comes to DIY, that's why I asked

The point is there's no reason to get a 12VO board without also getting the PSU to go with it. Boards aren't just going to magically all switch over overnight. There's actually no guarantee that 12VO will even be a thing in the consumer market. It's meant to help meet efficiency standards for business and government. There will be no mandate or even real impetus for normal consumers to switch.

[Guest]

On 6/21/2021 at 4:54 PM, Spotty said:

Interesting, I didn't realise Corsair was selling that. Judging by the cable looking like a snake just swallowed a rabbit they fit the DC-DC converters in to the cable sleeving? Inb4 everyone complains about how stiff the cable is in the middle. Hopefully no-one breaks it trying to force the side panel closed on it or while bending it in some weird angle to cable manage it.

Correct.  There's a boost converter in the middle of the cable to convert the +5VSB to +12VSB.  The rabbit in the middle is actually pretty flat.  Easy to hide.

 

[Guest]

2 hours ago, Chris Pratt said:

The point is there's no reason to get a 12VO board without also getting the PSU to go with it. 

Considering that most people will swap out their hardware once a year, but keep a PSU for about 10 years, it's perfectly reasonable to assume that someone would want to power an ATX12VO board with an ATX PSU.

 

[Spotty]

3 hours ago, 17030644 said:

What would be best? 12VB generated from 12V or 12VB using a boost converter fed with 5VSB?

 

Considering that the 5VSB rail is only rated at 2.5A in some PSUs

If you use the 12V rail you won't be able to provide standby power. The +12V switches off when the PSU goes in to standby mode. You could get around this by having the PSU always on by bridging the PS_On pin but that defeats the purpose of having a PSU in standby.

 

If the +5VSB rail is only 2.5A (12.5W) it shouldn't really matter. The power draw from the components during standby are still going to be the same. If your system is consuming 2W in standby then it'll still be consuming 2W, just instead of being 5V .4A it will be 12V .17A. To generate the 12V .17A it will be drawing .4A from the 5VSB rail of the PSU. Overall it shouldn't be a problem, unless there's something else I'm missing here?

[Chris Pratt]

45 minutes ago, jonnyGURU said:

Considering that most people will swap out their hardware once a year, but keep a PSU for about 10 years, it's perfectly reasonable to assume that someone would want to power an ATX12VO board with an ATX PSU.

 

No. It's not, actually. You're assuming that this is going to replace traditional ATX boards, and that's simply not the case. You'll still be able to buy ATX boards for the foreseeable future. 12VO is an alternative aimed squarely at the enterprise, not a replacement for ATX. There's not going to be a situation where you have a 12VO board and an ATX PSU, because you either simply shouldn't have bought the board, or you'd need to pair it with a 12VO PSU to actually attain the efficiency.

[Guest]

1 hour ago, Chris Pratt said:

No. It's not, actually. You're assuming that this is going to replace traditional ATX boards, and that's simply not the case. You'll still be able to buy ATX boards for the foreseeable future. 12VO is an alternative aimed squarely at the enterprise, not a replacement for ATX. There's not going to be a situation where you have a 12VO board and an ATX PSU, because you either simply shouldn't have bought the board, or you'd need to pair it with a 12VO PSU to actually attain the efficiency.

I disagree. We don't know what the retail ATX12VO landscape even looks like.  As far as we know, Intel could decide to make certain next generation tech (PCIe 5.0, DDR5, etc.) or sockets (LGA 1700) available only as ATX12VO.  Right now, all of the boards are Z490 and Z590 because that's what's available right now to build on.

 

[chebsy]

43 minutes ago, jonnyGURU said:

I disagree. We don't know what the retail ATX12VO landscape even looks like.  As far as we know, Intel could decide to make certain next generation tech (PCIe 5.0, DDR5, etc.) or sockets (LGA 1700) available only as ATX12VO.  Right now, all of the boards are Z490 and Z590 because that's what's available right now to build on.

 

I'm not disagreeing with you and would never dare to.  But how much control would intel have over how their next-gen chipsets are powered?  Would it be a legal/contract thing (any Z6XX sold must be 12VO or else), or could they prevent standard ATX power on a hardware level?  It would be difficult to see how the latter would be achieved but I look forward to your insight.  

[Guest]

42 minutes ago, chebsy said:

I'm not disagreeing with you and would never dare to.  But how much control would intel have over how their next-gen chipsets are powered?  Would it be a legal/contract thing (any Z6XX sold must be 12VO or else), or could they prevent standard ATX power on a hardware level?  It would be difficult to see how the latter would be achieved but I look forward to your insight.  

It's completely up to them.  They drive the ATX standards and they can call the shots on how future CPU and chipsets are used. Sure, motherboard partners can eventually do whatever they want, but it's a lot like Nvidia and new GPUs.  reference designs  come first and AIB versions are only available once the design becomes "virtual" (never knew why they called it that).  Even AMD is looking at ATX12VO at this point.

 

[aisle9]

1 hour ago, jonnyGURU said:

It's completely up to them.  They drive the ATX standards and they can call the shots on how future CPU and chipsets are used. Sure, motherboard partners can eventually do whatever they want, but it's a lot like Nvidia and new GPUs.  reference designs  come first and AIB versions are only available once the design becomes "virtual" (never knew why they called it that).  Even AMD is looking at ATX12VO at this point.

 

As long as there's a reliance on 5V SATA, I struggle to see the advantage here. The SATA power ports on the mobo take up more space than the 24-pin, and I would imagine an ATX12VO ITX motherboard would be just this side of impossible. Unless, of course, the plan is to phase SATA out entirely over the next few generations with a focus shifted towards having (hopefully a much less expensive) NVMe standard totally replace it in all applications, including el cheapo especials that today would still be booting off a hard drive. Either additional M.2 slots on the board or a huge price reduction on 2TB and 4TB drives...which was kind of the point of QLC, right?

 

You're completely tied into this, and I'm just a sap on the internet that reads articles sometimes. Are there other power-centric advantages to using ATX12VO, or does it really boil down just to what I constantly read about how a 10-pin connector saves so much space over 24-pin...without anyone mentioning that if you have 2-4 SATA adapter connections directly on the board, you've got no space savings at all?

[Chris Pratt]

8 hours ago, jonnyGURU said:

I disagree. We don't know what the retail ATX12VO landscape even looks like.  As far as we know, Intel could decide to make certain next generation tech (PCIe 5.0, DDR5, etc.) or sockets (LGA 1700) available only as ATX12VO.  Right now, all of the boards are Z490 and Z590 because that's what's available right now to build on.

 

We do know. For one, the platform has nothing do with it. Intel isn't just going to come out with a CPU or chipset that requires it, because it's inconsequential to both of those. They still get power as they always have; it's just moving circuitry from the PSU to the board. The components could care less.

 

Second, 12VO isn't some thing off in the distance. There's boards and PSUs out already, and notably they are niche products, because they serve a niche.

 

Again, this is not something intended to replace ATX. It's an alternative for businesses and governmental organizations that need to meet some of the more rigorous efficiency standards some countries are starting to enforce. That has zero impact on consumers, as they still have the freedom to choose what they want, and ATX will remain both the easy, cheap, and standard option, precisely because of things like you're talking about: having a 10 year old PSU that's still good.

[chebsy]

6 hours ago, Chris Pratt said:

We do know. For one, the platform has nothing do with it. Intel isn't just going to come out with a CPU or chipset that requires it, because it's inconsequential to both of those. They still get power as they always have; it's just moving circuitry from the PSU to the board. The components could care less.

 

Second, 12VO isn't some thing off in the distance. There's boards and PSUs out already, and notably they are niche products, because they serve a niche.

 

Again, this is not something intended to replace ATX. It's an alternative for businesses and governmental organizations that need to meet some of the more rigorous efficiency standards some countries are starting to enforce. That has zero impact on consumers, as they still have the freedom to choose what they want, and ATX will remain both the easy, cheap, and standard option, precisely because of things like you're talking about: having a 10 year old PSU that's still good.

I hate to appeal to authority, but if jonnyGURU thinks the enthusiast sector could move to ATX12VO to the extent that he would design and sell an adapter, I would take that to the bank...

 

If that's the real jonnyGURU anyway, I'm new to this forum so I don't know 

[Guest]

13 hours ago, aisle9 said:

You're completely tied into this, and I'm just a sap on the internet that reads articles sometimes. Are there other power-centric advantages to using ATX12VO, or does it really boil down just to what I constantly read about how a 10-pin connector saves so much space over 24-pin...without anyone mentioning that if you have 2-4 SATA adapter connections directly on the board, you've got no space savings at all?

It actually has very little to do with saving space.  In fact, it takes up more space on the motherboard.

 

What's driving this is Intel's initiative to make things as power efficient at low loads as possible.

 

I don't know who/why people are saying it saves space.  That's NOWHERE in the ATX12VO initiative/documentation. 

 

Quote

Computers are continuing to change and operating at lower idle (S0) power values. Beyond the trend for “green PC” reducing PC power consumption, Government Energy Regulations is one of the key reasons for pushing desktop computers to lower idle power values. Another reason is Microsoft* Modern Standby and the associate hardware state of S0ix. A generic term for Modern Standby used in government energy regulations is “Alternative Low Power Mode” or simply ALPM. These new power requirements have created new requirements for power supplies. In the ATX12VO (12V Only) Desktop Power Supply Design Guide, Section 1.1 provides a summary of these requirements. All ALPM features are supported by ATX12VO.

Designing green and more energy efficient computer systems are becoming increasingly critical even for desktop PC’s. Energy Regulations are forcing system level Power Reduction for future designs: CEC Tier 2 (July 2021), Japan Top Runner (April 2022), Energy Star v8 (Est. Q3 2020).

The power loss of a Power Supply Unit (PSU) is one of the major power consumers in a Desktop System @ Idle mode. Around 25-50% of total Desktop system power consumption is the PSU loss @ Idle Mode. Current Single Rail PSU designs have an efficiency of 70-76% @ 10W DC Load, while the current Multi-Rail PSU designs efficiency is in the range of 50-60% @ 10W DC Load.

Currently many large OEMs design a high percentage of their desktop systems using a proprietary Single Rail PSU. Channel and Gaming systems currently use Multi-Rail PSU design as this was the only Industry Standard PSU design.

There's more, but you get the point...

 

In fact, when Gamer's Nexus was drooling over how across the board efficient the Dell PSU they reviewed was, I had to email them and point out to them that the main reason for this was because it wasn't a multi-rail PSU.

 

Dell, HP, Lenovo are doing it today, not to "save space", but because they have efficiency requirements they need to meet and it's a lot cheaper to have a single output PSU and move your buck converters onto the motherboard.   I just wish they would have standardized a long time ago because now everyone is using a different connector to accomplish the same thing. 

 

8 hours ago, Chris Pratt said:

12VO isn't some thing off in the distance. There's boards and PSUs out already, and notably they are niche products, because they serve a niche.

Actually, you still can't buy the stuff.  The stuff you see in circulation was made specifically for testing, etc.  Essentially all "engineering samples" ("proof of concept" is what Intel is calling it).

8 hours ago, Chris Pratt said:

We do know. For one, the platform has nothing do with it.

We know that a platform that's still under development and does not exist in the wild beyond engineering samples is not going to be platform dependent? 

 

Intel is actually still in the process of tweaking ATX12VO due to revisions being made to PCIe 5.0 spec.  Because PCI-SIG is trying to allow add in cards to have 3x TDP power spikes for x # of ms

 

(why they can't just tell users to buy a bigger PSU, I don't know.  It's like they don't want to "scare off customers".  If you're buying a $1000+ graphics card, spend another $100 on a PSU for Pete's sake!  But I digress, that's a whole other migraine I have to deal with....)

 

 

Intel has concerns that they're not taking CPU power spikes into consideration as well.  So they're thinking about using the reserved pin of the ATX12VO connector as a signal wire that the PSU can communicate back to the board with, reporting current so the motherboard can "load balance" appropriately when these spikes occur.  

 

It should work similar to iMon in server PSUs:

Problem with this is... there goes those cost savings for not having multiple voltage rails in your PSU!  (sad trombone)

 

8 hours ago, Chris Pratt said:

It's an alternative for businesses and governmental organizations that need to meet some of the more rigorous efficiency standards some countries are starting to enforce.

Not sure where you got that from.  It's not "businesses and governmental organizations" needing to meet efficiency standards.  PCs built by system integrators are required to adhere to efficiency requirements.  First, it was only for PCs sold in California, but it seems that as of the beginning of next year, a number of other states are also adopting the standard, as well as Japan, etc.  That's folks like ABS, iBuyPower, CyberPowerPC, Origin, Maingear.....  PCs that people like us buy.  Not government entities. 

 

AMD is looking forward to the +12VSB aspect of the new platform because of the Type C connectors found on RX 6000 cards.  They want to be able to power that while in standby.  

 

[Juular]

34 minutes ago, jonnyGURU said:

that the main reason for this was because it wasn't a multi-rail PSU

Huh ... what ?

35 minutes ago, jonnyGURU said:

Because PCI-SIG is trying to allow add in cards to have 3x TDP power spikes for x # of ms

(why they can't just tell users to buy a bigger PSU, I don't know.  It's like they don't want to "scare off customers".

If you're buying a $1000+ graphics card, spend another $100 on a PSU for Pete's sake!

Yeah ... that would be interesting to say at least, but on a positive side since it would be in specifications PSU manufacturers would be able to actually make their PSUs to specifications, not just guessing how transient-heavy GPUs in a few next generations would be and what kind of OCP levels they should set to avoid 'Seasonic Focus'ing their PSUs.

[Guest]

10 minutes ago, Juular said:

Huh ... what ?

 

What?

 

Every time power passes through a circuit, it wastes energy.  And just like a PSU in it's entirety is less efficient at low loads, so are the DC to DC converters at low loads for the same reason.  

 

The DC to DC in a PSU has to be "one size fits all", while by moving the DC to DC to the load (on the mobo) you can scale the converter to only put out what's to be expected of it making it more efficient across a wider range of loads.  Example:  If you're supporting three SATA drives on a single connector, you know to make that converter capable of no more than 3A.

[electropical]

1 hour ago, jonnyGURU said:

In fact, when Gamer's Nexus was drooling over how across the board efficient the Dell PSU they reviewed was, I had to email them and point out to them that the main reason for this was because it wasn't a multi-rail PSU.

Did you also shoot them an email about that pre-built they praised with a Thermaltake Smart inside?