GPU TDP vs Heat/Temp

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gintama7888

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Hello, I'm trying to found out if GPUs with lower TDP will also run much cooler with the same cooling since they should produce less heat.
e.g. these 3 GPU's have different TDP ratings but I think they use identical heatsink/fan.
Asus 670 Mini - 170W TDP, 1x 8pin, 6.7"
Asus 960 Mini - 120W TDP, 1x 6pin, 6.7"
Asus 970 Mini - 148W TDP, 1x 8pin, 6.7"
GTX670 Mini is 170W but GTX960 Mini is only 120W, so you would expect the GTX960 Mini to run noticeably cooler than the GTX670 Mini(considering they have same heatsink/fan) in same condition.
But it's hard to tell the thermal difference between them just by looking at the results from different reviews, since the load temp would vary depending the application used to detect load temp, ambient temp, case/fans and CPU heatsink/fan used, etc.

Load temp of Asus GTX670/960/970 Mini from different reviews:
670 = 70C - http://www.techpowerup.com/reviews/ASUS/GTX_760_DirectCU_Mini/30.html
670 = 71C - http://www.guru3d.com/articles_pages/geforce_gtx_760_asus_directcu_mini_review,6.html
960 = 67C - https://youtu.be/XCXZLE-Y78k
970 = 44C - http://www.bit-tech.net/hardware/graphics/2015/01/15/asus-geforce-gtx-970-directcu-mini-review/8
970 = 74C - http://www.overclock3d.net/reviews/gpu_displays/asus_gtx970_mini_itx_rushkit/1

I'm building new ITX system on Lian Li PC-TU100 case and bought i7 4790S(65W TDP) instead of 4790(84W TDP) or 4790K(88W TDP) to reduce the case/overall temperature. I also have Asus GTX670 Mini(170W TDP) for the new build atm, but I'd buy Asus GTX960 Mini(120W TDP) if it will run noticeably cooler than the GTX670(despite the minimal performance difference).

Does anyone happen to have two different GPUs(i.e. different TDP/W) with same/similar heatsink/cooling? would you be able to check the load temp on each GPUs and post here? Thank you
 
Most GPUs these days have their fans controlled based upon the temperature of the GPU. Therefore, it's entirely possible/likely that in your example, a 670 and 960 will run at the same exact temperature with the same heatsink/fans, but the 960's will likely be spinning slower to maintain that temperature. Temperature is NOT a measurement of the amount of energy that a card uses - TDP is better for that (and not always fully accurate).

The amount that the internal case temperature will be increased based upon your GPU is more about the amount of energy (via heat) it is dumping into your case.
 
The larger the core, the easier it is to cool which benefits some older cards.
Newer cards using a smaller process for the GPU can use the same cooler and have the same TDP but will require the cooling fan to work harder to keep the same temp because the heat is produced in a smaller space and can only exit from that smaller space.

The same TDP will dump the same heat into the case.
 
Nenu said:
The larger the core, the easier it is to cool which benefits some older cards.
Newer cards using a smaller process for the GPU can use the same cooler and have the same TDP but will require the cooling fan to work harder to keep the same temp because the heat is produced in a smaller space and can only exit from that smaller space.
Click to expand...

That's not the only option.

Heat transfer is a function of temperature delta, and surface area of the chip, and thermal conductivity of the heatsink. So if you redesign the heatsink or TIM to be more conductive, you can get the same performance as before without having to turn the fans faster (for two chips of the same TDP, one smaller). If all you see if the fan, how do you know that that heatsink hasn't been redesigned? :D
 
I agree with the last two posters. Also, 50W of TDP difference (which is a maximum value, not a typical value) isn't that much difference.
 
defaultluser said:
That's not the only option.

Heat transfer is a function of temperature delta, and surface area of the chip, and thermal conductivity of the heatsink. So if you redesign the heatsink or TIM to be more conductive, you can get the same performance as before without having to turn the fans faster (for two chips of the same TDP, one smaller). If all you see if the fan, how do you know that that heatsink hasn't been redesigned? :D
Click to expand...

I didnt give options, I stated with the same cooler.
Thought I'd try not to confuse the op too much.
 
Nenu said:
I didnt give options, I stated with the same cooler.
Thought I'd try not to confuse the op too much.
Click to expand...

No, you were totally right, I was just pointing out that the OP may be making too many assumptions about this "same" cooler.

Have they seen a teardown for all three?
 
It should be noted that official listed TDP ratings do not necessarily have any basis in reality.
 
Thanks for some insightful infos, cos I never thought about the different GPU core sizes and how it effects the overall heat/temp(even on same cooler) due to conductivity etc.

However IF 670 and 960 had identical surface area, and therefore 960 runs noticeably quieter, then I would upgrade 670 to 960(since my main goal is to build quite and cool ITX system), or just replacing the heatsink to Arctic Accelero Mono Plus might be the best bet for cool & quite. http://www.arctic.ac/worldwide_en/accelero-mono-plus.html
 
Well the recent 290 X I bought has 2 x 8 pin connectors which is 150watts apiece and 75watts from the PCI Express slot which is 375watts of power the card can pull but it runs very cool at 65c thanks the TRI X cooler.
 
fanboy said:
Well the recent 290 X I bought has 2 x 8 pin connectors which is 150watts apiece and 75watts from the PCI Express slot which is 375watts of power the card can pull but it runs very cool at 65c thanks the TRI X cooler.
Click to expand...
You're confusing TDP with power consumption. TDP is the amount of energy (in this case, heat) represented in watts that needs to be dissipated to keep the electronic component within operating temperatures. While the two are related, they are not necessarily comparable due to the varying ways in which manufacturers measure TDP.
 
Amp's x Volts = Watts and no matter how you want to look at it heat is made by movement of power current and your only trying to keep that passive current level cooled by how much was engineered for the card to use .. changing of phase power design has a lot to with current and how it is better used and cooled.
 
Get a 970 with a blower. I just bought one yesterday. Hot air goes out the case.

You can also buy normal components and just undervolt them if they are too hot.
 
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