## Won't matter much to me.........

Message boards : Number crunching : Won't matter much to me.........
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Chilean
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Message 1382049 - Posted: 17 Jun 2013, 6:16:46 UTC - in response to Message 1381884.

One summer my ac went out and it got 106 in my living room where my cruncher is and it kept on crunching no problem. The way I understand it if my computer uses 300 watts to crunch it is not the same as 300 watts of heat because all the electricity is being used not to produce heat but to crunch with some heat as a by product. Similar to a 100 watt incandescent light bulb produces more heat than 100 watt florescent bulb which produces no heat. They both use 100 watts electricity one produces heat and the other does not. Computes are much the same they do all kinds of stuff but their design is not to produce heat. A 1500 watt computer does not produce as much heat as a 1500 watt space heater.

Correct me if I'm wrong, but most if not ALL of the electric power used by a PC is converted into heat.

It's not the same as an engine turning a certain % of the gas' potential energy into mechanical energy and the rest goes to heat. In CPUs, the mere fact of moving an electron (to compute) produces heat, P = I^2 * R.

CPUs use energy to "produce" something logical, not energy based, ergo, all the power it consumes must go somewhere (hint: heat).
This boggled my mind the first time I read it, could someone expand on this?
ID: 1382049 ·
Paul D Harris
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Message 1382079 - Posted: 17 Jun 2013, 7:55:28 UTC - in response to Message 1382049.

If all a pc did is convert it's emery into heat it would be very inefficient but pc are very efficient there fore less heat is produced much like a florescent light bulb that's all it is too it. You can not heat a room or make toast or light my cigar with a pc it is just too efficient. Now when I was in the USAF they had those old computers that used reel to reel computers the size of refrigerators and they had them by the dozen crammed into a room that had to be air conditioned because of the heat they produced but my pc in my living room produces very little heat my appliances such as my plasma TV and my clothes dryer and my refrigerator produce way more heat than my pc and yet they do not heat my hall or kitchen. The drier would heat some if I do not vent it outside.
ID: 1382079 ·
Clyde
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Message 1382098 - Posted: 17 Jun 2013, 10:28:06 UTC

P = I^2 *

Now I get it!
Those who cannot remember the past are condemned to repeat it.
--- George Santayana
ID: 1382098 ·
juan BFP
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Message 1382106 - Posted: 17 Jun 2013, 11:21:08 UTC - in response to Message 1382049.

I'm wrong, but most if not ALL of the electric power used by a PC is converted into heat.

You are not wrong, besides some power converted to others forms of energies, like mechanical moviment (fans), light(monitor & leds), electromagnetic radiation, etc. that could get some of the heat out and actualy dissipate it outside of your room. ALL you electric power use at the end will be converted in to heat. Nobody could fight against the law of entrophy. The only thing we could do is try to use a more eficient PSU, GPU´s etc. to use less Watt´s per WU, but each WATT used is a WATT converted to heat... And even Creditnew could fight against that!
ID: 1382106 ·
tullio
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Message 1382133 - Posted: 17 Jun 2013, 14:03:57 UTC - in response to Message 1382106.

Hard disks are converting electric power in motion. I have installed a solid state disk in my laptop and it generates less heat.
Tullio
ID: 1382133 ·
BilBg
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Message 1382148 - Posted: 17 Jun 2013, 15:51:03 UTC - in response to Message 1382079.

If all a pc did is convert it's energy into heat it would be very inefficient ...

You continue to not understand the laws of physics.

('efficient' PC is just a PC which draw less Watts for the same 'useful work' but it will still convert all those 'electrical Watts' to 'heat Watts'.
Get 100 'efficient' PCs, make them work hard and they will heat the room to unbearable levels (end 'exactly' to the amount they draw from the mains).

If you measure they draw 100*100 = 10000 W it will be the same as if you use 10000 W heater.
If they idle at 10 W each: 100*10 = 1000 W = at idle state they will heat as if you use 1000 W heater.
)

The only way I see those 'electrical Watts' will not equal the 'heat Watts remaining in the room' is if some of the energy escapes the room in a form of electromagnetic radiation (radio waves, light, infrared) or mechanical waves (sound, vibration)
(but still 'electrical Watts' = 'heat Watts', just not all 'heat Watts' remain in the room)

Some say fans/HDD/CD turn so electrical energy is converted to mechanical (kinetic) energy.
But for this mechanical energy it takes only a few seconds to be all converted to heat (if you switch OFF the computer fans/HDD stop after a few seconds)
So electrical energy is only added to sustain the turning and is added in the same amount which fans/HDD 'lose' by mechanical -> heat conversion.

- ALF - "Find out what you don't do well ..... then don't do it!" :)
ID: 1382148 ·
Chilean
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Message 1382153 - Posted: 17 Jun 2013, 16:03:55 UTC - in response to Message 1382079.

If all a pc did is convert it's emery into heat it would be very inefficient but pc are very efficient there fore less heat is produced much like a florescent light bulb that's all it is too it. You can not heat a room or make toast or light my cigar with a pc it is just too efficient. Now when I was in the USAF they had those old computers that used reel to reel computers the size of refrigerators and they had them by the dozen crammed into a room that had to be air conditioned because of the heat they produced but my pc in my living room produces very little heat my appliances such as my plasma TV and my clothes dryer and my refrigerator produce way more heat than my pc and yet they do not heat my hall or kitchen. The drier would heat some if I do not vent it outside.

Just because all of the power consumed goes to heat, it does not mean it is inefficient per se.

Take for instance my laptop's CPU, it's TDP is 45 watts, so let's just say it draws 45 watts from the wall under full load. Alright, those 45 watts go directly into heat, BUT, in the process, it's performing millions of instructions per second. Thus the term, performance per watt.

In terms of converting electric power into some kind of "useful" energy (such as an engine turning potential energy from gas to me rollin' down the highway), PCs are 0% efficient.

My old athlon 64 6400+ kept my room pretty warm at night (along with my GPU), that CPU alone had a TDP of 125 watts!
My laptop now, has a TDP of 45 watts, and computes about 4-6 times more using less energy. THAT's efficiency!
ID: 1382153 ·
tullio
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Message 1382187 - Posted: 17 Jun 2013, 16:54:09 UTC

The new top gun in the top500 list, China's Tianhe-2, reaches 33.86 petaflops in the Linpack benchmark and delivers 1901.5 Megaflops/watt. Just figure its electric power consumption and the cooling power it needs.
Tullio
ID: 1382187 ·
William
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Message 1382194 - Posted: 17 Jun 2013, 17:05:44 UTC

The discussion somewhat reminds me of the guy who wanted to cool down the room by leaving the fridge door open.

Mark, sure you can't leave the whole farm crunching, but maybe you can keep the smallest rig (measured in powerconsumption/heat) up or something?

Weren't you experimenting with automated power up and down of the rigs at some point as well? Boinc can also be set up to only crunch parttime - when not crunchin they shouldn't produce too much heat...
ID: 1382194 ·
kittyman
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Message 1382196 - Posted: 17 Jun 2013, 17:11:50 UTC - in response to Message 1382194.

The discussion somewhat reminds me of the guy who wanted to cool down the room by leaving the fridge door open.

Mark, sure you can't leave the whole farm crunching, but maybe you can keep the smallest rig (measured in powerconsumption/heat) up or something?

Weren't you experimenting with automated power up and down of the rigs at some point as well? Boinc can also be set up to only crunch parttime - when not crunchin they shouldn't produce too much heat...

Yes, as the temps get warmer, I'll start shutting some rigs down during the day.
I'll not go down entirely.

I can set the bios to auto restart some rigs at night when I am away at work and the temps drop. Then I have to shut the PSU off so they don't restart if it's not going to cool down enough at night.

And I know Boinc can be set up to only crunch in certain time slots, but at that point the power consumed at idle would be entirely wasted. Depending on the computer, that can still be 150-300 watts or so.

It'll continue to be a battle for me all summer long.
But, the kittyman shall not give up entirely.

Meow.
A day without cats is like a day without sunshine.
I speak meow, do you?

Have made friends in this life.
Most were cats.
ID: 1382196 ·
Paul D Harris
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Message 1382208 - Posted: 17 Jun 2013, 17:44:02 UTC

I am not talking about the physics of entropy. What I am talking about is how people supposedly heat their homes with a few pc. My cruncher consumes about 700 watts or so yet the heat out does not equal the heat from a 700 watt space heater it is considerable less. I can put my hand behind the computer case it will not burn my hand and it does not feel like a 700 watt space heat as a space heater will burn my hand when placed close up to it. Space heaters have caused fires and it takes the fire department to put out such fire. I have never heard of the fire department putting out a pc fire. Have any one ever worked in a physics lab and done entropy experiments? Like in a voltage regulator 12 volts in and 5 volts out and the excess electricity is converted into heat it is wasted electricity. I know I can not heat my living room much less the desk area by my pc it simply will not happen I need a space heater to heat my living room not my pc heating my living room. My pc might warm my hand but it certainly will not heat my working area of my pc.
ID: 1382208 ·
betreger

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Message 1382218 - Posted: 17 Jun 2013, 18:07:10 UTC - in response to Message 1382208.

If you were to measure to heat output with more precision than your hand you would find it does produce the same heat as a 700 watt space heater or you will have found a new principal of physics. All energy ends up as heat, eventually.
ID: 1382218 ·
Paul D Harris
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Message 1382223 - Posted: 17 Jun 2013, 18:13:55 UTC - in response to Message 1382218.

I tell you what you can heat with your pc and I will heat with my space heater.
ID: 1382223 ·
bill

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Message 1382225 - Posted: 17 Jun 2013, 18:21:49 UTC

And the world is flat once more.
ID: 1382225 ·
Chilean
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Message 1382253 - Posted: 17 Jun 2013, 19:57:07 UTC - in response to Message 1382208.

I am not talking about the physics of entropy. What I am talking about is how people supposedly heat their homes with a few pc. My cruncher consumes about 700 watts or so yet the heat out does not equal the heat from a 700 watt space heater it is considerable less. I can put my hand behind the computer case it will not burn my hand and it does not feel like a 700 watt space heat as a space heater will burn my hand when placed close up to it. Space heaters have caused fires and it takes the fire department to put out such fire. I have never heard of the fire department putting out a pc fire. Have any one ever worked in a physics lab and done entropy experiments? Like in a voltage regulator 12 volts in and 5 volts out and the excess electricity is converted into heat it is wasted electricity. I know I can not heat my living room much less the desk area by my pc it simply will not happen I need a space heater to heat my living room not my pc heating my living room. My pc might warm my hand but it certainly will not heat my working area of my pc.

I thought voltage regulators helped maintain a constant voltage level. Aren't you talking about a transformer? Transformers heat up due to Foucault currents and copper resistance (as well as hysteresis and so forth), but they, unlike PCs, DO some kind of transformation from one kind of energy to another, in where whatever inefficiency they have turns into heat, and the rest goes into useful stuff (in the case of the transformer and rectifier in the case of your PSU) it is a nice lowered DC voltage.
I might be wrong, but if your PSU is 95% efficient, then for every 100 watt that goes thru it, only 95 watt will come out at the other end, and the other 5 watt will turn into... heat!

PCs on the other hand compute (which is a logical thing, not a new form of energy) at the expense of electric usage which turns completely into heat. There's no way to turn 1 watt into 1+1=2. Yes, the calculation itself does indeed need electrons going thru transistors which in itself uses "1 watt", but that 1 watt will end up as heat... not in 1+1=2.

Have you ever left your heatsink without a fan? It gets REALLY hot to the touch.

If your PC draws 700 watts from the wall, then it will heat up your room as a 700 watt space heater. Try experimenting: Turn off your PC and turn on your 700 watt space heater and I assure you, having all the rest of the variables the same, it'd be the same as having your PC on and the space heater off.
ID: 1382253 ·
bill

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Message 1382265 - Posted: 17 Jun 2013, 20:43:32 UTC - in response to Message 1382253.

One point to remember, a seven hundred watt space heater
puts out 700watts of heat all the time when turned on.

A pc with a 700watt power supply doesn't.

Edit

An applicable article

http://www.guru3d.com/articles_pages/geforce_gtx_460_review_%28roundup%29,13.html
ID: 1382265 ·
Alinator
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Message 1382268 - Posted: 17 Jun 2013, 20:58:21 UTC - in response to Message 1382265.

One point to remember, a seven hundred watt space heater
puts out 700watts of heat all the time when turned on.

A pc with a 700watt power supply doesn't.

Unless it's crunching flat out 24/7 (more or less) that is.

In any event, there is absolutely no difference between X watts of heat coming from a computer and a space heater rated at X watts, regardless of what some people think. ;-)
ID: 1382268 ·
bill

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Message 1382273 - Posted: 17 Jun 2013, 21:08:47 UTC - in response to Message 1382268.

One point to remember, a seven hundred watt space heater
puts out 700watts of heat all the time when turned on.

A pc with a 700watt power supply doesn't.

Unless it's crunching flat out 24/7 (more or less) that is.

If somebody is running a 700watt power supply at
a maximum output of 700watts they are foolish and

In any event, there is absolutely no difference between X watts of heat coming from a computer and a space heater rated at X watts, regardless iof what some people think. ;-)

Agreed. Watts is watts.
ID: 1382273 ·
Alinator
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Message 1382276 - Posted: 17 Jun 2013, 21:13:12 UTC - in response to Message 1382273.

LOL...

Regarding the power supply, that much is certain!

Unless your job is to do failure analysis on the design, that is. ;-)
ID: 1382276 ·
BilBg
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Message 1382357 - Posted: 18 Jun 2013, 3:08:13 UTC - in response to Message 1382208.

My cruncher consumes about 700 watts or so yet the heat out does not equal the heat from a 700 watt space heater it is considerable less.

Did you measure it in real time?
It may really consume only 200 watts.

(If your PSU is rated '700 W' this does not mean your computer really "consumes about 700 watts"
The same: if your stereo music system say "total RMS power of 100 W" this does not mean you use that power (Volume to Max) all the time.
)

- ALF - "Find out what you don't do well ..... then don't do it!" :)
ID: 1382357 ·
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Message boards : Number crunching : Won't matter much to me.........