will power supplies ever add a higher voltage?

[tynopik]

with some supplies capable of putting out truly ridiculous amperage on the 12V line (like the Ultra X3 2000-watt with 150A across 2 rails), will there ever be a move to bump up the supply voltage to keep things more reasonable?

or since this is about the theoretical max before tripping circuit breakers, will companies will just continue to deal with it?

 

[heymrdj]

It is intriguing. Do to their complexity and electronics, it's on the drawing board to now make 24, 36, and maby 48 volt cars. All in the name of more electricity.

 

[mpilchfamily]

There is no need for higher voltages. As it is the 12V going to everything then gets reduced down to 3V or less in most cases. Back in the day of the P4 they upped in voltage to the CPU to 12V adding the P4 connector to the PSU. This was done so that you could have better regulated and more stable power fro the CPU. No item in the PC could really benefit from the same kind of transition. In a time when conserving energy is the in thing to do adding higher voltages means beefing up the voltage regulators in the system. This translates into more heat and lower efficiency of the system.

Adding a higher voltage doesn't mean you have more power. The heavy drain that all the tech gadgets for cards is on the amperage not the voltage. A car battery and Alternator can only offer so much amerage right now. If you need more power for electronic items in the car then you need a higher output battery and a larger alternator to keep things running.

 

[thecoolnessrune]

mp is right. Remember that all that 12V power is eventually turned down to whatever your CPU's vCore is. CPU's use like 90-95 amps of current in their small little voltage. The question is what would bring the best efficiency overall? A reduction once more to an all 5V system? A reduction to 3.3V? Marketing wise, this would be a bad move since converting 120V AC down to 3.3V DC would be highly inefficient. However, less powerful voltage regulators could be used on the boards, thereby reducing the heat generated by the system but increasing it in the PSU load.

 

[tynopik]

> Adding a higher voltage doesn't mean you have more power

well i know that, but it does mean less resistance loss in the power cables and less need for really thick wires

of course it does transfer more expense to the board

 

[jonnyGURU]

Right. But your not putting more current down the same wires, you're putting the same or even less current down multiple wires.

PCIe connectors are a prime example of this:

6-pin PCIe support up to 75W. If the graphics card needs more than that, you have two PCIe connectors: 150W. If the graphics card needs more than this, you switch out a 6-pin for a 150W 8-pin. Now you have 225W delivered via the PCIe connectors.

Raising the voltage and reducing the current will only reduce the number of connectors required, but increase hardware cost because more regulation has to be done on the board.

As far as the "safety" aspect of something like a 150A +12V rail... that's what they have PSU's with multiple +12V rails. No, the Ultra X3 isn't one of them, but that's why they're out there.

 

[tynopik]

i understand exactly what you're saying and i'm sure your right

but it just puzzles me that they jumped from using the 5V line for CPUs and stuff to the 12V line

all the arguments you make for not having anything higher than 12 could also be made for not moving from 5 to 12

why not just have a ton of extra 5V connectors? that will reduce hardware cost because less regulation has to be done on the board

obviously that's not what happened, but it just seems strange the way it worked out

 

[jonnyGURU]

Give and take without any drastic changes to the ATX standard.

They went from 5V to 12V for the reasons you cite. Higher voltage, lower amperage.

But the +12V rail ALWAYS existed. When CPU's went from 5V to 12V rail, you didn't have to buy a new PSU. If your PSU didn't have the 4-pin CPU power connector, you could use a Molex to 4-pin adapter. Start regulating CPU voltage off of a 24V rail and everyone's going to have to buy a new PSU when they replace their motherboard!

And then of course... the added cost of regulating that much further down for the Vcore.

Same argument is true of single DC voltage PSU's. You could have a more efficient, cheaper PSU if it only had to regulate one output voltage. But then all of your component costs will go way up because more regulation would have to be done at the component.

Your argument makes sense. It's just not pratical. Take a look in a (real) server room some time. There's a lot of expensive propietary equipment running off of 24V and 48VDC power supplies. Why can they do it? They're not adhering to an industry wide, consumer level compatibility standard like PC's have to. All they have to make sure of is if the chassis fits inside an 18" rack!

 

[Modelworks]

What I would really like to see is them just going to one voltage.
Say 5volt.
When the standards were devised it was costly to convert 5v to higher voltages.
Now though its very cheap to do it, converters priced under 1.00 can take 5v and output up to 37v . It would make power supply design really simple.

Problem is you have to have all the current hardware change over to that, and thats not going to happen without some serious effort.

 

[Super Nade]

Having one voltage makes sense, but remember that the trend with CPU's is that VCore is decreasing while the current per phase is increasing. Computer SMPS designs have to follow this trend as if the voltage is high, then the MB has to do a lot more work in the step down phase of the CPU VRM (DC-DC conversion).