Can max TDP be used to calculate wattage draw?

[Goodcreature]

When I was putting together a parts list for a build, this question came up. I've looked around for an answer, but there seems to be some disagreement. Many people say that since TDP measure heat dissipation, and doesn't take into account power consumption, it can't be used accurately. Others say that the actual power consumption of certain components isn't all that much, and so TDP provides a pretty good figure.

Do you guys use TDP to calculate your wattage draw? If not, what DO you do?

 

[salvage-this]

I normally work off the power requirements of my GPU since most reviewers are using power hungry platforms to bench the GPU. If you want a better idea of just what the processor takes Guru3D normally has it on their CPU reviews.

http://www.guru3d.com/articles_pages/core_i5_3570k_review,10.html

BTW this is a good explanation of TDP

https://www.youtube.com/watch?v=yDWO177BjZY

 

[Goodcreature]

Those are very thorough reviews! Thanks for posting the link; I will definitely be referencing those in the future.

Installing a component and actually measuring the power draw is definitely the best way to go, but there's no way to find that out just by using the manufacturer's specs?

 

[Okedokey]

Thermal Design Performance is always going to be higher than the power consumption, as some of the energy is converted into work, and the rest into heat. So TDP is a good conservative estimate of wattage power consumption.

 

[StrangleHold]

When I was putting together a parts list for a build, this question came up. I've looked around for an answer, but there seems to be some disagreement. Many people say that since TDP measure heat dissipation, and doesn't take into account power consumption, it can't be used accurately. Others say that the actual power consumption of certain components isn't all that much, and so TDP provides a pretty good figure.

Do you guys use TDP to calculate your wattage draw? If not, what DO you do?

TDP is pretty close. But under full, load peak power is usually about/around 10/15% more (can even be more) then TDP. TDP is nothing but what processor makers uses. So CPU coolers manufacturers can get a idea of on average of how much heat to dissipate.