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The test

So basically what we'll do today is really simple. We want to look at three things heat,  noise and performance.

Let's handle heat and performance the first. So what we'll do is very simply monitor the IDLE and load temperatures of the GPU. We'll monitor this with the help of our home grown Rivatuner. First the we'll monitor the card completely at default settings and in the second stage we'll overclock it to it's max and monitor everything again.

As you can see the GPU is idling at roughly 32 Degrees C. That's really nice and a good indication of what a Peltier unit can do. I do believe this is conservative though. In essence you can take a Peltier unit way below zero. Now since condensation is a huge factor you do not want to do that. 30 Degrees C is okay but geez .. why not 10 Degrees C ? At that temperature condensation is not an issue yet you' could overclock the GPU really far.

Anyway, we startup a run of 3DMark05 (the three game-demo sequence) to have a look how heat builds up in the GPU. Surprisingly as you can see .. it's not very good. Heat very quickly builds up towards 50 Degrees C making this card merely 15 degrees C less warmer opposed to a standard cooler. Wattage .. system was utilizing 279 watts at peak. Not that bad at actually ... but at this stage I am not impressed as I was convinced the GPU would remain below 40 Degrees C. I mean hey .. this is peltier.

For the next stage we'll now overclock the GPU core (and only the GPU core to see how far we can push it). Now please understand the card we are testing today is a GeForce 7900 GTX 512MB, one of the most flexible to tweak and overlock cards ever. Since we use peltier we expected lower temperatures and thus the ability to at the very least overclock towards 725 MHz. This unfortunately was not the case. Have a look.

The minute we started overclocking the temperature rose towards 53-Degees C. At 725 MHz we got lockups and artifacts. So despite using this form of cooling we are not able to squeeze an additional amount of performance out of the card compared to traditional cooling as we are stuck at 700 MHz.

So concluding here is whilst 52-53 Degrees C is a nice temperature, it's nothing very special, most definitely not enough for a massive overclock. For that we need sub-30 Degrees C temperatures.