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Google Calls For Power Supply Design Changes
Raindance writes "The New York Times reports that Google is calling 'for a shift from multivoltage power supplies to a single 12-volt standard. Although voltage conversion would still take place on the PC motherboard, the simpler design of the new power supply would make it easier to achieve higher overall efficiencies ... The Google white paper argues that the opportunity for power savings is immense — by deploying the new power supplies in 100 million desktop PC's running eight hours a day, it will be possible to save 40 billion kilowatt-hours over three years, or more than $5 billion at California's energy rates.' This may have something to do with the electricity bill for Google's estimated 450,000 servers."
You can say goodbye to USB powered devices. An example would be the canned drink cooler.
Thanks,
Jim
Considering how many machines Google has to maintain, I'm surprised they just don't order motherboards and power supplies to their own spec, and then allow the mfrs to distribute the design to others who request it. They're big enough and have enough whuffie that they can start a trend all by their lonesomes.
A lot of telco equipment is designed to run on -48 volts DC and PC and server power supplies are readily available at this voltage.
The advantage of -48 over 12 volts is that there will be less loss through resistance and smaller conductors can be used. Of course, there is a greater risk of electric shock, but I would think -48 would be pretty safe.
48 volts is also the standard for Power over Ethernet (IEEE 802.3af). This may not be compatible, though, since telcos run -48, not +48, though some equipment can operate with either (though some cannot).
This post is encrypted twice with ROT-13. Documenting or attempting to crack this encryption is illegal.
Actually I would bet that Google servers DON'T have a video card, and that all of them have RJ-45 SOL support (or something like it). The reason being that Google has admitted that they fully embrace the commodity distributed server system. Google will periodically host talks at my university where they explain all this in [too much] detail.
:)
Basically, when a machine fails, it is pulled from the rack and replaced with an identical machine with a cookie cutter image. Kinda like the Borg
When a box fails it is probably instantly detected by some machine monitor and taken offline (think: the 'crop' tenders in the Matrix I). The sysadmins arent going to waste time plugging a video cable into the rack... just pull it. Toss the box into a repair queue and let the tech's put a video card into it if needed. Remeber: 100's of machines fail for them every day. That's a fact from the Google talk in 05.
There are 10 types of people in the world. Those who understand binary and those who do not.
In the old days, disk drive motors and fans. But many of these now run on 5V, hence the cheap USB-powered drive cases out there. Chips at CMOS power levels run at 3.3v, TTL is 5v, but hardly anything runs at 12v anymore. It seems to me that if they'd just pick their hardware carfully, they could run their entire server rack off of 5v+- rails.
You are correct that hard drives generally use just 5V, but the rest of your points are not even close. Modern CPUs require lower voltages, higher current, and tighter regulation, which is why DC-DC power supplies are now on motherboards instead of running directly from an ATX supply.
Furthermore, running a rack of servers on 5V rails would be absolutely absurd. Do you have any idea what the amperage would be? The bus bars would have to be several inches thick, the transmission loss would be enormous, and if you accidentally shorted them.... forget it!
Something like 48VDC might work but then you lose out on all the economies of scale driven by the 110/240VAC standard.
Just match the power supply to the motherboard and be done with it. Standardizing on one voltage is impractical, and besides, how would it improve "efficiency"?
Most of the postings so far have it all wrong. Google is not proposing 12VDC into a desktop PC or 12VDC distribution within the data center. What they're proposing is that the only DC voltage distributed around a computer case should be 12VDC. Any other voltages needed would be converted on the board that needed it.
This is called "point of load conversion", and involves small switching regulators near each load. Here's a tutorial on point of load power conversion.
It's been a long time since CPUs ran directly from the +5 supply. There's already point of load conversion on the motherboard near the CPU. Google just wants to make that work off the +12 supply, and get rid of the current +5/-5/+12/-12 output set.
The Mac Mini will boot and run on a 12-volt supply. It only takes 17v so that it can provide Firewire power.
-jcr
The only title of honor that a tyrant can grant is "Enemy of the State."
One standard, applied equally across the entire range of products.
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The one used by the majority of DC electric devices, not just computers. The one compatable with existing external power supplies such as solar, home gas powered generators, your car battery, etc.
If motherboards were designed to run on 12v DC you could put a socket on the back of the case and jack into anything that gave you 12v DC. You could take your home desktop straight to the RV, boat, or cabin in the woods running off a turbine in the little stream or the windmill; without inverters.
I've been talking about his shit for decades. I've talked about it here. You might almost think that Google:
http://hardware.slashdot.org/comments.pl?sid=1977
KFG
The early S-100 systems (Altair, Imsai, Poly, Northstar) used linear supplies and ran unregulated DC on the S-100 bus. Most designers aimed for +8 to +9 volts to feed the onboard +5 volt regulators (and the3 volt or so headroom for 7805 regulators). Can't think of any that ran high current AC on the bus. Some systems, such as the Poly, ran a squared-up 60 HZ signal for real-time clocks.
The heat losses in S-100 on-card linear regulators were immense! That and the weight of the (linear) transformers helped make the Apple ][, with its switching power supply, so popular (I still have an old Poly power transformer; makes a great doorstop).
Some mainframe computers used the scheme mentioned by others -- polyphase high-frequency AC distribution. High frequency (think 800 Hz) power transformers are small and efficient; that's why switching supplies run at high frequencies (in the hundreds of KHz range).
Efficiency is not only about wasting less power, it's about generating less heat!
Efficiency is not only about wasting less power, it's about generating less heat!Which is of course exactly the same. In the end all the energy you put into a computer turns into heat. The energy wasted in the power supply turns into heat in the power supply, and all the heating of the power supply is energy wasted rather than used to supply the computer.
Do you care about the security of your wireless mouse?