[q] Heatoutput and Power Consumption

[rcarlos243]

I was wondering if anyone has done some testing regarding system unit power consumption of stock air cooling and liquid cooling.

 

According to the first law of Thermodynamics "Energy can neither be created nor destroyed. It can only change forms. In any process, the total energy of the universe remains the same. For a thermodynamic cycle the net heat supplied to the system equals the net work done by the system". With that in mind we could presume that all of the energy has to end up somewhere, either in the original form or in a different from. It is plausible to determine the amount of energy(power draw) in a system, the energy lost(as waste heat), and the efficiency of the system.

 

Considering that Nvidia GTX 78x xx/Titan, AMD R9 290/x with stock cooler generate 80~95c heat under load we could assume that a lot of the energy is being wasted as heat which translates to excessive power consumption. Anandtech measured a system unit total power consumption on Crysis 3 under load to be about ~400w and that is without overclocking the GPU or using multiple graphics cards.

 

So why does it matter? According to U.S. Energy Information Administration, California's electricity cost for residential costs 18.12 Cents per Kilowatthour on Aug 2014. Assuming you are gaming 5 hours a day 7days a week it would cost $10 per month and $131 per year.

 

While that doesn't seem much, what if you are running more than 1 system unit on a place or do multiple graphics cards or overvolt the gpu or game for extended periods of time? To makes matters worse according to an article about average electricity prices around the world by shrinkthatfootprint in 2011 countries such as Australia, Japan, Germany, Spain and Denmark cost 25+ Cents per Kilowatthour.

 

 

Considering that doing a GPU Liquid Cooling is now cheap thanks to NZXT G10 + AIO Liquid cooler I hear people claim that graphics card like the R9 290x got an temperature improvement from 95c to 52c under load.

 

I was wondering how that kind of improvement in temperature translates into power draw savings.

[harrybob141]

Look at it this way: If the day is 40deg c and you are a carpenter, you won't be working as efficiently as a day that is 20deg c.

 

To my knowledge same for computer components 

 

I would say the cooler the better.

[rcarlos243]

Look at it this way: If the day is 40deg c and you are a carpenter, you won't be working as efficiently as a day that is 20deg c.

 

To my knowledge same for computer components 

 

I would say the cooler the better.

 

I understand that but has anyone actually done some testing and see what the actual power draw before and after Liquid Cooling?

[Interfectorem]

The power draw is the same. The heat dissipation is more efficient however. Still using the same amount of watts. The same amount of heat is being produced, it's just that it's being carried away a lot faster into the water. 

[d3sl91]

The power draw is the same. The heat dissipation is more efficient however. Still using the same amount of watts. The same amount of heat is being produced, it's just that it's being carried away a lot faster into the water. 

Yeah +1.

 

Wattage will be the same, just better dissipation. The newer 900 series still run warm temperatures, but they use way less power and perform much better than older versions, and AMD. 

[rcarlos243]

The power draw is the same. The heat dissipation is more efficient however. Still using the same amount of watts. The same amount of heat is being produced, it's just that it's being carried away a lot faster into the water.

Has that ever been tested?

AFAIK transistors in theory will consume less power at the same switching speed if they are kept at a lower temperature.

[Interfectorem]

Has that ever been tested? AFAIK transistors in theory will consume less power at the same switching speed if they are kept at a lower temperature.

Probably has, but not that I know of. On an air cooler, all you have taking away heat from the GPU is a hunk of metal plates and some air moving through them. With water cooling, you have some metal (waterblock) but you also have water in direct contact with that metal, on top of that, you have that water in contact with more metal (radiator) which is being absorbed by moving air. If power consumption is loewr, it will be very negligible. It's simply just taking heat away much more efficiently.

[Archangel1994]

it would cost $10 per week and $131 per year.

You have a funny amount of weeks in a year

[rcarlos243]

You have a funny amount of weeks in a year

I meant per month not per week

[Archangel1994]

I meant per month not per week

Then that's about right with the rounding of numbers and so forth :3

[Godlygamer23]

Not necessarily related, but very interesting.

The Math Behind GPU Power Consumption and PSUs

 

Credit in link goes to Tom's Hardware.