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.

The Biostar GeForce 9600 GT is a very quiet card in idle, but under load it gets a bit noisy. While it is far from being loud, the fan can be heard spinning from outside of the case with heavy load. Since the GPU temperature under load is around 65°C I think there is some potential left by adjusting the fan control algorithm. A slightly higher temperature at the benefit of a quieter card would not hurt the product.

The coil noise I encountered during the Zotac GeForce 9600 GT Amp! review is still there but almost inaudible. You have to put your ear next to the fully stressed card to hear it.