News Report: 12V-Only Power Supply Spec Launching This Year

alextheblue

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Initially, the transition will only hit system integrators, so the DIY space will likely continue using the existing 12V ATX design for quite some time.

The idea behind ATX12VO is that it ditches the 3.3V and 5V rails, leaving the power supply's only job as to provide 12V to the system's components. This simplifies the power circuitry design and, thus, lowers the production cost of components.
OEMs have been doing this for years... at least HP has. In the short term I don't think it actually saved them any money, as the mainboard supplied the other voltages, so the circuitry was just moved to the motherboard. In the longer term, yeah it should save them a little bit, as they eradicate any need for legacy voltages/devices.

I guess eventually we'll get to that point in the DIY market, and when we need 5V or 3.3 we'll have to use adapters that have built-in step downs or something. But that probably will take years.

Side note, I hope OEMs adopt the 12VO standard instead of the proprietary crap. Using standard PSUs as replacements in certain OEM boxes has been annoying for years, in many cases I've had to either use adapters, or cut and splice.
 
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OEMs have been doing this for years... at least HP has. In the short term I don't think it actually saved them any money, as the mainboard supplied the other voltages, so the circuitry was just moved to the motherboard. In the longer term, yeah it should save them a little bit, as they eradicate any need for legacy voltages/devices.

I guess eventually we'll get to that point in the DIY market, and when we need 5V or 3.3 we'll have to use adapters that have built-in step downs or something. But that probably will take years.

Side note, I hope OEMs adopt the 12VO standard instead of the proprietary crap. Using standard PSUs as replacements in certain OEM boxes has been annoying for years, in many cases I've had to either use adapters, or cut and splice.


Yea Dell has been doing this for about 4 years now. it makes it a pain though from a IT point of view. Lucikly i do have 1 PSU for testing, but they also are doing a different form factor now on their PSUs so I can't even use a 24 pin adapter to their 8 pin adapter that Dell uses unless i leave the PSU hanging out. For OEM's I don't see any issue with this so long as there can be 3rd part supplies of power supplies as well. On the main stream/custom side I don't want that to ever dissapear. Some of us still run multiple hard drives ( I have 12!) and i just don't see all those amps being able to go though the motherboard.
 
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setx

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Moreover, various USB devices are also slowly starting to adopt 12V as their input voltage to speed up charging, and chances are that there will be a day when all new USB devices are built on using 12V rather than 5V.
Do you even understand what you are writing about? First of all, nowhere USB specification even mentions power voltages besides 5V. It's either proprietary extensions that are going to die soon or USB-PD. And with USB-PD any other voltage besides 5V are, surprise, optional addition to 5V.

So, 'USB' device that require 12V won't work with almost all current hardware and even then will need to negotiate 12V over 5V power first.

Based on strong backward compatibility of USB, 5V is definitely going to stay for decades there.
 

InvalidError

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So, 'USB' device that require 12V won't work with almost all current hardware and even then will need to negotiate 12V over 5V power first.
External interfaces will have to go optical at some point due to how difficult it becomes to maintain signal integrity through multiple connectors and cables of non-trivial length. I wouldn't be surprised if USB5 introduced an optical connector spec with 12V default voltage.
 

d0x360

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yeap we don't need any of those legacy power connectors, the vast majority need more m.2 slots and that's it

Im going to disagree on that one. I have multiple SSD's in my system, Windows is on its own, then all my games are on others BUT I still have 2 HDD's for things like my download folder, my documents folder and general storage of basically anything that isn't a game.

Also we don't need more m.2 slots we need SSD's that are larger and cheaper. If happily replace all my current SSD's with a single large drive but the price is still prohibitive.

Lastly there is the reliability question. You can either have that power coming from a PSU that's easily switched out should it die or have all that power running through the motherboard and potentially frying it should some fault occur. It's unlikely to happen but more likely than a PSU doing the same.
 
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alextheblue

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On the main stream/custom side I don't want that to ever dissapear. Some of us still run multiple hard drives ( I have 12!) and i just don't see all those amps being able to go though the motherboard.
For DIY though even with a 12VO PSU, you'll still have extra connectors that do NOT run through the mainboard. They'll just be 12V only. So there's no need to worry... if you have hardware that runs at 5V, for example, you could use external step-downs. It could be a board that has multiple connectors, or inline "line lump" adapters.

Either way that is YEARS down the road, and by then all the HDDs (if you still use them at that point) will be built for 12V and handle everything on their own circuit board. So these adapters would only be used for legacy components.
 

InvalidError

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Perhaps, but not for like keyboards, mice, sound devices, or a plethora of other USB-based peripherals and devices.
Most of the "plethora of other devices" I can think of beyond thumb-drives are higher power than what can comfortably be delivered over 5V USB and have to be self-powered.

Intel made many mistakes with the USB spec to shave costs initially that are coming back to bite the standard in the ass, 5V is one of them. 5V made sense back then when most low-speed stuff worked straight off 5V, does not make sense in more modern days where everything needs DC-DC converters to get that down to 0.8-3.3V anyway and would be ~10% more efficient working from 12V instead.

I don't know for you but for me, had USB been a 12V standard, I'd probably have about a dozen fewer proprietary AC adapters around my desk.
 

alextheblue

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That and another 40+ PCI-e lanes on the CPU or motherboard.
I mean... why? Seriously that's a lot of bandwidth, especially on a PCIe 4.0+ platform. You're proposing a large price hike for motherboards and processors, that would impact everyone in the mainstream. The ones who need all those lanes can pay for it themselves - in other words, If you really need that many PCIe lanes, you need to get a HEDT platform.
 
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daglesj

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I mean... why? Seriously that's a lot of bandwidth, especially on a PCIe 4.0+ platform. You're proposing a large price hike for motherboards and processors, that would impact everyone in the mainstream. The ones who need all those lanes can pay for it themselves - in other words, If you really need that many PCIe lanes, you need to get a HEDT platform.


Yeah but if folks want 6+ M.2 slots (like they have 6 or so SATA now) how's it gonna happen?

As for price hikes I remember when a high end motherboard cost $60. It wasn't all that long ago.

Welcome to the new world.
 

InvalidError

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Yeah but if folks want 6+ M.2 slots (like they have 6 or so SATA now) how's it gonna happen?
It isn't going to happen on mainstream platforms, very few normal people need more than one full-speed NVMe SSD (for most of the mainstream, I suspect most computers have only one HDD or SSD) and motherboards don't really have space for more than three NVMes either unless you put them on PCIe riser cards. On cards, you could have a PLX PCIe router to split a PCIe 4.0x4 slot between however many NVMes you can fit on the card or have up to four NVMes wired as 4.0x1 instead of using a $50+ chip.
 

daglesj

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It isn't going to happen on mainstream platforms, very few normal people need more than one full-speed NVMe SSD (for most of the mainstream, I suspect most computers have only one HDD or SSD) and motherboards don't really have space for more than three NVMes either unless you put them on PCIe riser cards. On cards, you could have a PLX PCIe router to split a PCIe 4.0x4 slot between however many NVMes you can fit on the card or have up to four NVMes wired as 4.0x1 instead of using a $50+ chip.


Now if I'd have said that, you'd all be saying "Speak for yourself...we are all enthusiasts and want NVMe up the back passage and beyond! 60 PCI-e lanes or give me death!!!" Etc. Etc.

The cost of the average retail motherboard is going up and up so...

Folks can't make up their minds who they are or what they want.
 

bit_user

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As for price hikes I remember when a high end motherboard cost $60. It wasn't all that long ago.
Never happened. In July of 2004, I paid Newegg $169 for an ASUS P4C800-E DELUXE motherboard. Incidentally, that was the only motherboard that ever died on me.

Anyway, whatever you're remembering, that wasn't a high-end motherboard, by any definition.

Welcome to the new world.
...er, welcome to reality?
 

daglesj

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Never happened. In July of 2004, I paid Newegg $169 for an ASUS P4C800-E DELUXE motherboard. Incidentally, that was the only motherboard that ever died on me.

Anyway, whatever you're remembering, that wasn't a high-end motherboard, by any definition.


...er, welcome to reality?


2004 eh? That's nice. I'm talking 10 years before that...
 

bit_user

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2004 eh? That's nice. I'm talking 10 years before that...
You said:

I remember when a high end motherboard cost $60. It wasn't all that long ago.

Not "all that long ago"? 25+ years is an eternity, in the PC industry. In 1994, the fastest CPU available was a 100 MHz Pentium (no MMX, even!). LCDs, GPUs, and SSDs weren't even a thing. Even if you're right (and I should note I'm quite skeptical about that), it was so long ago as to be completely irrelevant.
 

gaaah

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Won't this have major implications for UPS designs? I mean, why take the 12VDC of your UPS batteries, invert it to AC, supply the AC it to your power supply, only to have your power supply convert it back to 12VDC to use on your motherboard? The UPS will still need an inverter to charge the batteries of course, but then actually using that stored 12VDC should/could be more direct and efficient.
 

InvalidError

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Won't this have major implications for UPS designs?
Makes no difference for normal applications, you'd need PSUs designed to take external DC power to bypass the input stage and even if you bypassed the high voltage regulator, you'd still need a buck-boost DC-DC converter to regulate battery's 10V empty under load to 14.5V end-of-charge to 12V+/-5% and you get ~10% losses there. Also, for significant loads, you'd want a 24V storage system so you only need a simple efficient buck converter over the entire battery voltage range instead of a more complex and less efficient buck-boost one.

For most people, the computer runs on AC power 99(.9)% of the time and the extra cost of increasing efficiency while on backup power by 5-10% isn't worth the expense of a dedicated DC-DC backup system. Also, you'd still need to provide power to the monitor(s) and any other necessary external peripherals that require external power if you want to actually be able to use your PC.

BTW, with modern PSUs capable of delivering 100% output on 12V using DC-DC converters off the 12V rails to generate the 3.3V and 5V rails, you could hypothetically power a system by back-feeding power directly into the 12V rail as long as the PSU isn't inhibiting them when AC-side power is missing, so you could say modern systems are already sort of 12VO as far as DC backup power requirements are concerned..