Arctic Accelero Hybrid 7970 Liquid Cooling System review

 So in this segment of the article we'll be looking at the cooling performance under game load for both the reference and now HYBRID cooled card.

Above, you can see a screenshot, two actually. To the left you can reference cooling performance. Your ambient temperature is 32~35 Degrees C with the reference cooler and a good 77 Degrees C when fully under stress.

Now to the right you can see the Arctic Hybrid cooler installed. The temperature drop is massive. We looped 3DMark 11 for half an hour and then fired a stress test at the GPU three times (this is how we measure game temperature performance). As you can see, in idle we average out at 25 Degrees Celsius and 42 Degrees under full game stress. These are outstanding results.

You need to know that we tested with an ambient temperature of 18~19 Degrees C. If you live in a country where it is much warmer then the coolant will be warmer as well. This can have an effect of 5 to 10 Degrees C on your coolant performance. So please do be aware of that. But then you'd be looking at sub 55 Degrees C temps under hefty game load. Next to that -- if it were placed inside the PC that ambient temperature will have an affect as well.

We can compare the results a little with a handful of R7970 based cards we have tested that all have custom air based cooling. Not one card comes close to what the Arctic Hybrid cooling solution offers. The next best in line is the TwinFrozr IV cooler form MSI.

Graphics card noise levels

When graphics cards produce a lot of heat, usually that heat needs to be transported away from the hot core as fast as possible. Often you'll see massive active fan solutions that can indeed get rid of the heat, yet all the fans these days make the PC a noisy son of a gun. Do remember that the test we do is extremely subjective. We bought a certified dBA meter and will start measuring how many dBA originate from the PC. Why is this subjective you ask? Well, there is always noise in the background, from the streets, from the HD, PSU fan etc etc, so this is by a mile or two an imprecise measurement. You could only achieve objective measurement in a sound test chamber.

The human hearing system has different sensitivities at different frequencies. This means that the perception of noise is not at all equal at every frequency. Noise with significant measured levels (in dB) at high or low frequencies will not be as annoying as it would be when its energy is concentrated in the middle frequencies. In other words, the measured noise levels in dB will not reflect the actual human perception of the loudness of the noise. That's why we measure the dBA level. A specific circuit is added to the sound level meter to correct its reading in regard to this concept. This reading is the noise level in dBA. The letter A is added to indicate the correction that was made in the measurement. Frequencies below 1 kHz and above 6 kHz are attenuated, whereas frequencies between 1 kHz and 6 kHz are amplified by the A weighting.

For each dBA test we close the PC/chassis and move the dBA gun 75 cm away from the PC. Roughly the same proximity you'll have from a PC in a real-world situation. Above, the dark blue bar is the IDLE (desktop mode) results where the GPU hardly has to do anything.

LOAD noise wise we do not have to complain a single bit either. The fans are rotating at a set/fixed RPM. Roughly 39 dBA is the noise pressure we measure. For the card in a fully stressed status (in-game) that simply is silent -- we can hardly hear the cooling solution work at all.

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