GeForce GTX 570 SLI review

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. I'm doing a little try out today with noise monitoring, so basically 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 not a precise 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 1kHz and above 6kHz are attenuated, where as frequencies between 1kHz and 6kHz 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 a PC in a real-world situation.

We deliberately put the cards close together in the system, as most of the motherboards currently in use will need to be configured that way. This means that the upper graphics card will get way less airflow. The one card heats up to roughly 80 Degrees C and the vapor chamber cooler cooler starts to spin up.

In SLI mode we do not get bad DBa levels returned once the GPUs really start to stress, roughly 42 maybe 43 DBa if the cards go really nuts. This means in the background you can hear fan and airflow, but very acceptable.