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Why Do Computers Use So Much Energy?

blogs.scientificamerican.com

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Re: Why Do Computers Use So Much Energy?

#141

Post by 8bitsrule »

lucideer wrote: post #12

> Precise estimates vary, but currently about 5 percent of all energy consumption in the U.S. goes just to running computers 30% goes on transport. > the human brain is a computer. This particular computer uses some 10–20 percent of all the calories that a human consumes So society's computer uses 5 percent and our own, evolved over millions of years, uses up to 20. I'm not saying computers can't or shouldn't be made…

For anyone heating their home/office in the winter, the energy consumed by their computer effectively has zero cost.

The computing done is value added to energy-use that would otherwise dissipate through the walls and ceiling. Those of us in northern latitudes should be lucky enough to have a couple of servers in the closet helping to pay for heating.

Re: Why Do Computers Use So Much Energy?

#142

Post by kingaillas »

lucideer wrote: post #12

> Precise estimates vary, but currently about 5 percent of all energy consumption in the U.S. goes just to running computers 30% goes on transport. > the human brain is a computer. This particular computer uses some 10–20 percent of all the calories that a human consumes So society's computer uses 5 percent and our own, evolved over millions of years, uses up to 20. I'm not saying computers can't or shouldn't be made…

>So society's computer uses 5 percent and our own, evolved over millions of years, uses up to 20.

Organic brains are also learning and doing language/image/sound processing that far exceed society's computer capabilities.

Re: Why Do Computers Use So Much Energy?

#143

Post by AgentOrange1234 »

Sohcahtoa82 wrote: post #134
NickM wrote: post #31

Earlier quoted context omitted.

Phones are much less powerful than PCs, but they feel comparably fast because most software developers waste exactly as much performance as they can get away with. The phone app developers are forced to write better, faster code than the PC app developers, just as PC app developers ten years ago were forced to write better code than PC app developers are today.

> Phones are much less powerful than PCs, but they feel comparably fast I beg to differ. My Droid Turbo is powered by a 2.7 Ghz quad-core CPU, yet often is incredibly slow. If I want to open Waze and enter and address to navigate to, it's often 10-15 seconds from the time I tap the Waze icon on the launcher until the apps is loaded and the on-screen keyboard has presented itself for typing. There are significant stut…

There’s a lot to blame — the software bloat, delivery mechanisms, user-hostile decisions that prioritize ads, and all the rest. But clock rate is truly meaningless as a performance measure when the underlying architecures are different...

Re: Why Do Computers Use So Much Energy?

#144

Post by ced »

8bitsrule wrote: post #141
lucideer wrote: post #12

> Precise estimates vary, but currently about 5 percent of all energy consumption in the U.S. goes just to running computers 30% goes on transport. > the human brain is a computer. This particular computer uses some 10–20 percent of all the calories that a human consumes So society's computer uses 5 percent and our own, evolved over millions of years, uses up to 20. I'm not saying computers can't or shouldn't be made…

For anyone heating their home/office in the winter, the energy consumed by their computer effectively has zero cost. The computing done is value added to energy-use that would otherwise dissipate through the walls and ceiling. Those of us in northern latitudes should be lucky enough to have a couple of servers in the closet helping to pay for heating.

Yeah, but who moves their computers outside of the closet in the summer? Then we have a larger AC bill to cover, and that's less efficient than heating.

Re: Why Do Computers Use So Much Energy?

#147

Post by analog31 »

ohiovr wrote: post #146

The reason computers use energy is because transistors have a finite signal rise time and are bound by ohms law. This is unlikely to ever change.

Indeed, but smaller transistors (less capacitance, thus less charge transfer) and lower voltages can reduce the power consumption of digital circuits. Also, more efficient software could reduce the amount of switching that has to occur. And I suppose one has to consider the power consumption of some peripherals such as LCD back-lighting.

Long ago I had an internship where we were developing a battery powered microprocessor based gadget. We had a prototype with a knob for the clock speed, and we slowed down the clock until the thing started being noticeably slow. Then we chose fixed components for the same clock speed. That's how we optimized battery life.

Note that my thinking is based on relatively simplistic CMOS processors. I don't know how this applies to higher performance computers in cell phones and laptops, with dynamic memory and other goodies.

Re: Why Do Computers Use So Much Energy?

#148

Post by gear54rus »

noxToken wrote: post #57
gear54rus wrote: post #47

Earlier quoted context omitted.

Don't know if you're trolling or not, but I fully agree. So much time could be saved by making the networks and internet ASCII-only

What if a client/user doesn't read/write English?

teach them one international language from the start of their life

Re: Why Do Computers Use So Much Energy?

#149

Post by xxs »

noir_lord wrote: post #74
orev wrote: post #66

Earlier quoted context omitted.

If your laptop consumed that much power it would be too hot to use on your lap and also would probably damage whatever surface you put it on. Just because a power supply has a max rating of X Watts doesn’t mean it’s always using that much. Even then, 200w for a laptop is an enormous amount. Maybe you meant LED bulbs that emit the equivalent light of a 100w bulb? That would be much closer to standard laptop power cons…

Indeed. I have a Thinkpad that has an i7-7700HQ, that's a 35W TDP beast and even under very heavy load I still get 90 minutes out of a 72 watt-hour battery and it gets pretty warm (and the TP has excellent cooling), 200W would melt your legs.

Intel TDP is a sham - it's based on the published non-turbo frequency which is 2.8GHz.

My primary laptop has its CPU undervolted (offset) by whopping 170mv, effectively around 30% lower power consumption.

Re: Why Do Computers Use So Much Energy?

#150

Post by markhahn »

dna transcription is a computation? bah. any computer uses about 10% of its capital cost in power annually. is that really a lot? sure, if you run it for 10 years, but the real sin there is running such an inefficient computer in year 9. running it for 3 years is a small deal.

sure, we pay a high power cost for reliable, deterministic, digital and synchronous computation. but we designed it that way, for that reason. we don't want unreliable or non-deterministic or approximate or whenever computation.

no question that some practices waste power. but we're doing just fine: power per computation (and probably more importantly, for communicating with memory and other systems) is coming down fast. move along, usual moore's law-like behavior, less to see each year...

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