Fan Noise

In the past years users would accept everything just to get more performance. Nowadays this has changed with people being more aware of the fan noise and power consumption of their graphic cards.
In order to properly test the fan noise a card emits we are using a Bruel & Kjaer 2236 sound level meter (~$4,000) which has the measurement range and accuracy we are looking for.


The tested graphics card is installed in a system that is completely passively cooled. That is passive PSU, passive CPU cooler, passive cooling on the motherboard and Solid-State HDD.
This setup allows us to eliminate secondary noise sources and test only the video card. To be more compliant with standards like DIN 45635 (we are not claiming to be fully DIN 45635 certified) the measurement is conducted at 100 cm distance and 160 cm over the floor. The ambient background noise level in the room is well below 20 dbA for all measurements. Please note that the dbA scale is not linear, it is logarithmic. 40 dbA is not twice as loud as 20 dbA. A 3 dbA increase results in double the sound pressure. The human hearing is a bit different and it is generally accepted that a 10 dbA increase doubles the perceived sound level.

When designing their card, it seems AXLE forgot to adjust the fan settings in the VGA BIOS to work best with the Arctic Cooling cooler. In both idle and load the card runs at 40% fan speed, which is the lowest fan speed defined the BIOS. This is a clear indicator that there is some untapped potential for silence in the fan.

As the card is now, it is quite noisy in both idle and load. A huge difference to other GTX 460 cards on the market, which are generally very quiet.

I did my own testing regarding the potential of the cooler with the right BIOS settings and modified the BIOS to run at 2% fan speed in idle and 15% speed under load. This resulted in an idle temperature of 35°C, which is the same as the idle speed at 40% ! Under load with 15% fan speed I saw 76°C under load - 63° with the stock BIOS at 40%, so not that much of an increase either. At such a fan speed setting the card would be the quietest midrange card on the market today - inaudible in idle, barely audible under full load: three slots justified.