Thursday, January 23rd 2020
Pure 12V PSU Standard, Named ATX12VO, Debuts Later This Year
Back at CES, at the FSP booth, we spied an inconspicuous-looking PSU with a curious 10-pin connector in place of the 24-pin ATX. The FSP500-30AKB turned out to be the first public exhibit of a the pure 12-Volt PC power supply standard being pushed by Intel, which is called "ATX12VO," which abbreviates Advanced Technology eXtended 12-Volt Only. According to the specification, the PSU only puts out +12 V and 12 Vsb voltage domains, and does away with the 5 V, 5 Vsb, and 3.3 V domains. This greatly simplifies the design of PSUs, as PCs of today don't use too many power-hungry 5 V or 3.3 V devices (such as half-a-dozen mechanical hard drives). The PC will still need 5 V for interfaces such as USB, but VRM on the motherboard will be responsible for DC-to-DC switching of 12 V to those lower-voltage domains. It's also likely that the motherboard will now put out a handful SATA power connectors.
Intel could debut ATX12VO within 2020 via its next-generation desktop platform, which features a 10-pin connector instead of 24-pin. It remains to be seen if the company could help the transition from current PSUs to the new standard by having its motherboard partners include a 24-pin to 10-pin adapter of some sort. In addition to the 10-pin connector, ATX12VO PSUs will put out two other purely-12 V connector types: 8-pin/4+4 pin EPS and 6+2 pin PCIe power. The EPS connector powers the CPU VRM, while the PCIe connector powers add-on cards, such as graphics cards. 4-pin Molex connectors could also be put out, but those will only feature 12 V pins (the 5 V pins will be absent).
Source:
CustomPC
Intel could debut ATX12VO within 2020 via its next-generation desktop platform, which features a 10-pin connector instead of 24-pin. It remains to be seen if the company could help the transition from current PSUs to the new standard by having its motherboard partners include a 24-pin to 10-pin adapter of some sort. In addition to the 10-pin connector, ATX12VO PSUs will put out two other purely-12 V connector types: 8-pin/4+4 pin EPS and 6+2 pin PCIe power. The EPS connector powers the CPU VRM, while the PCIe connector powers add-on cards, such as graphics cards. 4-pin Molex connectors could also be put out, but those will only feature 12 V pins (the 5 V pins will be absent).
102 Comments on Pure 12V PSU Standard, Named ATX12VO, Debuts Later This Year
Splitting things up also allows higher current to reach the device, while keeping things safe per wire, although there's a trade-off here as well to make sure it's as efficient as possible. Then there's things like impedance that could reduce cause some other funny things to happen, such as Voltage reduction, which you don't want either.
But 4.5 Watts per USB3 port and 8 Watts per M.2 slot add up pretty fast and I bet the MB manufactures hate the idea of putting a ton of additional VRMs on the boards.
There are absolutely zero electrical problems. It all just about the habbit.
But I guess this has the same fate as the BTX standard: won't gain much traction outside the OEM space and will die eventually...
This is something I've done for a client, very simple, very effective and it can do at least 5V/2A. That PCB is 60x40mm and it's just so it can accommodate enough connectors on the other side. Admittedly this would not be how a motherboard would be designed, as they'd use a more powerful setup that could power all the 5V outputs, but it's hardly as if this is going to be a major issue for the board makers, compared to doing the CPU VRM.
As an example, see link below.
www.gigabyte.com/Embedded-Computing/GA-IMB310TN-rev-10 Actually, most modern notebooks are 19V ;) But it is cheap. The parts needed are few cents. I don't get it, why are so many people in this thread making this out to be something really complex, when it's not?
Another project, this is a pico-ITX board at 100x72mm with 12V input that can deliver 5V and 3.3V to the pin headers. How can such a tiny board do it when some people here claim there isn't space on a mini-ITX board?
I am joking, but it isn't too far from the truth :D
As for voltage converters, we shouldn't forget the existence of monolithic DC-DC converter blocks like this one from Murata. 5V4A output from 12V in a 9x10.5x5.5mm package. That's essentially the size of a CPU VRM inductor alone. Add it to the board and you can power at least a few USB ports. Sure, this one is expensive and relatively low power, but there are cheaper ones, and they definitely get cheaper if you're buying ten thousand a pop.
Nonetheless, people need to stop thinking this will make motherboards noticeably more expensive. It won't. The components needed are well known to manufacturers - they can even likely reuse CPU VRM components if they want to - compact and readily available. Also, comparing on-board component sizes to PSU component sizes is an invalid comparison, as PSUs are always overbuilt; they are built to cover a wide variety of hardware configurations, while an on-board supply would be tailored to the components on that board. Even looking at a lowly 500W unit like the most recent PSU review here on TPU, it supports 17A on its 5V rail and 18A on its 3.3V rail. Both of those are massively overkill for most modern usage scenarios, and could thus be downsized significantly if moved to the motherboard. A 500W PSU needs to be built to handle both a gaming setup with a fast CPU and GPU and a single SSD and a file server with a low-power CPU, no GPU and a heap of mechanical HDDs and SSDs, meaning they are built for a wide variety of different loads. With this standard we can reduce the overhead here and move towards more tailor-made solutions better suited to their intended use. Not true. There are several ways in which this improves efficiency. None are dramatic improvements, but they all matter:
- No cable losses transferring 3.3V and 5V from the PSU to the motherboard (and likely shorter cables for any devices needing power from the motherboard, like HDDs)
- Simpler, cleaner PSU designs due to only producing a single output voltage (this is the biggest one by far)
- Universal adoption of DC-DC conversion for lower voltages (doesn't apply to modern high-end PSUs that already do this, but many still don't)
- Better sizing of DC-DC converters for the load in question, hitting efficiency sweet spots more easily
- Proliferation of bespoke converters for power-hungry components (
Definitely not far from the truth. Delivering a few amps for USB and SATA really doesn't require a lot of space.Another pro for this, btw: moving to motherboards needing voltage converters for USB could easily lead to a proliferation of USB-PD support on the same boards - it's not that much more difficult building a 12V-to-5/9/12/15/20V system than a 12V-to-5V one.
Gosh... space? The whole backside of any motherboard is mostly deserted, with some caps under South bridge and CPU.
Let's say 8 USB ports on the IO and 4 internal each 900mA. Plus 7 PCIe slots with each 3A and two M.2s with 2.5A each. That's over 50 Watts for the 5V and 80 Watts for 3.3V supply.
Putting additional VRMs of that dimensions on an already feature packed PCB is tricky and costly.
However, long gone are the days of 500mA or 900mA USB connectors, as most boards deliver 1-2.4A per USB ports these days, simply because people expect to be able to charge their mobile devices from the ports on their PC.
@Valantar That Murata part is insanely expensive though, so that's not likely to find its way into regular PCs as yet. Also, high Amps on the minor rails is a way that the PSU makers have managed to "uprate" their PSUs for years, since it's the combine Wattage that's put on the box at the end of the day...
There are PMU's capable of delivering many amperes of current... multi rail, multiple regulation and safety, low noise.
Haven't you thought that we have now wall chargers with GaN? Tiny things with a primary for mains voltage pumping out 60W?? HELLOOO people? What is this?
It amuses me really...
I have a new argument.
How about putting less RGB PWM drivers on the board, how we got place for them then? :laugh:
Still, you're going from 12V, so it's not expensive or tricky.
This is a new part from TI that can do 40A and it's a 5x7mm chip. That means it can be placed pretty much anywhere on the motherboard. Yes, this part is a bit on the pricey side, but it was the first thing I found doing a quick search and I'm sure it's far from the only part like this.
www.ti.com/product/TPS543C20A
Dev board size
You are suffling the same components from the PSU to the MB and ending up swapping them twice as fast.
Current decent PSU designs are already DC-2-DC. I would rather have all the filtering and protection in the PSU housing, instead of using my brand spanking new motherboard effectively as power distribution panel. You would also need a lot of digital short circuit protection and filtering added to the VRM of the motherboard, while also adding a lot of complexity to the PCB it self, so memory and PCIe traces have proper shielding.
Not sure if I'm ready to buy 200USD entry level motherboards cause they need to be manufactured on 8-10 layer PCBs...
www.exagan.com/en/
Also you are in EU? 2 years of warranty... who cares if you change them anyways? It's kinda a hot topic now... I have to take a shovel and take all my chargers to the bin because of that as they all had gone EOL.