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norwegian
Premium
join:2005-02-15
Outback

12 volt power supply computer


I'm looking at organizing a computer for a friend who wants a 12 volt system for her energy efficient house. Why does she run a computer on 240 volts when a 12 volt dc/dc can be built.

Anyone with ideas?
--
The only thing necessary for the triumph of evil is for good men to do nothing - Edmund Burke



FizzyMyNizzy

join:2004-05-29
New York, NY

Maybe it is her way of saying "I want an iPad3" ?..



Vchat20
Landing is the REAL challenge
Premium
join:2003-09-16
Columbus, OH
reply to norwegian

Check out the store on Mp3car.com, they have plenty of power supply related hardware designed for 12V DC systems (ie: Your average automobile). My only note to advise of is if her power is unregulated, make sure the power supply hardware you use on the computer provides a regulated supply.
--
I swear, some people should have pace-makers installed to free up the resources. Breathing and heart beat taxes their whole system, all of their brain cells wasted on life support.-two bit brains, and the second bit is wasted on parity! ~head_spaz



norwegian
Premium
join:2005-02-15
Outback

Her house has been on a 12 volt battery system for some 20-30 yrs with a generator back-up, I think it is all regulated.

Mp3car.com seems to give a few ideas to work with though, cheers.

iPad3?
Seems to miss the question all together. She is updating to digital tv and wants a simple box system that sits beside the TV and plays the odd movie (you're almost scaring her with technology that no doubts needs a computer or power point to charge it). A power point doesn't eliminate the 240v plug in the wall. And this project is to be wired to quite a battery of batteries, excuse the pun.
--
The only thing necessary for the triumph of evil is for good men to do nothing - Edmund Burke


daveinpoway
Premium
join:2006-07-03
Poway, CA
kudos:2

Here (»www.powerstream.com/DC-PC-12V-500.htm ) are some PC power supplies which operate from 12 VDC. I'm sure there are others; this is what came up from a quick Google search.



norwegian
Premium
join:2005-02-15
Outback

said by daveinpoway:

Here are some PC power supplies which operate from 12 VDC. .......from a quick Google search.

Thanks, your google is better, I had mini boards/plugs and no steel framework - these linked seem to fit the bill. A little more money than standard supplies it seems, but worth the outlay all the same I think.


Ken Peterson
Premium
join:2000-12-08
kudos:3
reply to norwegian

Holy mackeral! $310 for a 12v ATX power supply? That seems like a very expensive option! It would be cheaper to get a DC to AC pure sine power inverter to plug the PC into that. A marine unit might fit the bill nicely, plus also give her options for other 110vac units which require a regulated power.



norwegian
Premium
join:2005-02-15
Outback

This house has all the options already.

The owner knows of the motherboard and drive voltages enough to ask - can I have a 12 dc /12 dc power supply running a computer.

This is the question raised here.

Note:
1. Regulating is fine.
2. Inverters or convertors for that matter are not part of the topic.
The house has these already in place.
240 volt (Aust standard mains) is not to be in this project, there is a perfect win 7 machine already, but would like to avoid 240v if 12v is sufficient.
3. Money boils down to total cost v's the wattage needed to run said project, the house has battery, solar, wind and genset for power supply, genset is only used if 240 volt gear needs to be run for an extended period.

What can be set up in a small box?
Not sure RasberryPI is quite enough, although worth a look at.
Anything under micro-atx I gather would allow enough of the minimal extras to run the basics, mini-itx or something similar?
--
The only thing necessary for the triumph of evil is for good men to do nothing - Edmund Burke


sk1939
Premium
join:2010-10-23
Mclean, VA
kudos:10
Reviews:
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Mini-ITX or Micro-ATX are probably your limits, or a barebones system like this that has an external power supply: »www.newegg.com/Product/Product.a···56101121



norwegian
Premium
join:2005-02-15
Outback

It looked okay till I read the power supply specs - it uses a mains power supply.

Just wondering, it dropped to 19 volts for the dc side, is it going to be too hard to have something running off 12 volts including an optical drive, can't see much more than a hdd, as some onboard chipsets will be fine for graphics and not sure what else other than a couple of usb ports and an ethernet connection.


sk1939
Premium
join:2010-10-23
Mclean, VA
kudos:10
Reviews:
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Yes, because you need to step it down further than that. There are three main voltages in a PC; 12V, 5V, and 3.3V, and you need to be able to provide all of them.

For example a Molex connector has the following,

Pin 1 Yellow +12 V
Pin 2 Black Ground
Pin 3 Black Ground
Pin 4 Red +5 V

While a Berg has

Pin 1 Red +5V
Pin 2 Black Ground
Pin 3 Black Ground
Pin 4 Yellow +12V

A SATA power connector has

1 3.3 V
2
3
4 Ground
5
6
7 5 V
8
9
10 Ground
11 Staggered spinup/activity
(in supporting drives)
12 Ground
13 12 V
14
15

or

— Coding notch
1 3rd Device presence
2 2nd 5 V
3 2nd
4 2nd Manufacturing diagnostic
5 1st Ground
6 1st

A PCI-e Power connector provides 12V and the ATX (20/24pin) connector has all three voltages. So the answer is that you can't run a computer straight off of 12V, you need a power supply to step down to 5V and 3.3V regardless.



norwegian
Premium
join:2005-02-15
Outback

I understand power supply, it isn't about having or not having one - more on what is the minimum needed to run a 12 volt set up. The RasberryPI will cover the client needs, but is a virtual project, not a micro-itx with a little more features that can be mounted in a small media box.


sk1939
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join:2010-10-23
Mclean, VA
kudos:10
Reviews:
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·Verizon FiOS

Minimum needed is basically a power supply that can run on 12V. Depending on how strict your power requirements are, I recommend something like this: »www.google.com/products/catalog?···oQ8wIwAg



norwegian
Premium
join:2005-02-15
Outback

Similar to what I was looking at earlier - »www.mini-box.com/picoPSU-160-XT

A mini-box power supply.

So it is this or the over priced self-contained supply for $315, regulated n all?

I'd almost want to look at powerstream for reliability for more.
However this model you suggest has me intrigued, I need to look at a calculator first to work min and max for likes and needs?

Is 90 to 160 standard for these?

I remember Dave's topic and 150 I think it was?
--
The only thing necessary for the triumph of evil is for good men to do nothing - Edmund Burke


sk1939
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Mclean, VA
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Reviews:
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Well the math for a Mini-ITX system with an Intel-2400S, 1 PCI card, Green HDD, DVD-RW, and 4 USB devices is around 156W min, meaning the recommended is 200W or so.

The self-contained power supply is pricey, but at the same time probably built to better standards. At the same time though, the price difference is considerable. If a PICO dies, you could replace it potentially 2 more times before hitting the cost even mark between them.

90, 120, 160, and 200 I think are the standards. For your uses I suggest these two:

»www.mini-box.com/M4-ATX?sc=8&category=981

»www.mini-box.com/PW-200M-DC-DC-power-supply


daveinpoway
Premium
join:2006-07-03
Poway, CA
kudos:2

"If a PICO dies, you could replace it potentially 2 more times before hitting the cost even mark between them."

Something to think about, however: If the failing power supply damages something else (motherboard, hard drive, etc.), this could change the equation very quickly.



norwegian
Premium
join:2005-02-15
Outback

I will have to discuss this option as a starting point. Because of the nature of the system, blowing power supply even on 12 volts might be of concern.

This is not for a business with insurances that can help/tax claims etc, but even if those options are available, security over less expense might be a need, we are not talking a young school student or recent leaver, we are talking a mature person who will not want it to let go within a year or 2....I would hope to get a similar time frame as the standard atx supply, generally speaking.
--
The only thing necessary for the triumph of evil is for good men to do nothing - Edmund Burke



cdru
Go Colts
Premium,MVM
join:2003-05-14
Fort Wayne, IN
kudos:7
reply to sk1939

said by sk1939:

Well the math for a Mini-ITX system with an Intel-2400S, 1 PCI card, Green HDD, DVD-RW, and 4 USB devices is around 156W min, meaning the recommended is 200W or so.

I just built an Intel DH61AG mitx mobo, Intel G620T Pentium CPU, mSATA card and several USB wireless adapters that is running off a 65W laptop power supply. This goes along with reviews (57.1 watts max using an i5 proc).