We have changed our method of measuring noise levels. We have built a system inside a Lian Li chassis with no case fans and have used a fanless cooler on our CPU. The motherboard is also passively cooled. This gives us a build with almost completely passive cooling and it means we can measure noise of just the graphics card inside the system when we run looped 3dMark tests.
Ambient noise in the room is around 20-25dBa. We measure from a distance of around 1 meter from the closed chassis and 4 foot from the ground to mirror a real world situation.
Why do this? Well this means we can eliminate secondary noise pollution in the test room and concentrate on only the video card. It also brings us slightly closer to industry standards, such as DIN 45635.
KitGuru noise guide
10dBA – Normal Breathing/Rustling Leaves
20-25dBA – Whisper
30dBA – High Quality Computer fan
40dBA – A Bubbling Brook, or a Refridgerator
50dBA – Normal Conversation
60dBA – Laughter
70dBA – Vacuum Cleaner or Hairdryer
80dBA – City Traffic or a Garbage Disposal
90dBA – Motorcycle or Lawnmower
100dBA – MP3 player at maximum output
110dBA – Orchestra
120dBA – Front row rock concert/Jet Engine
130dBA – Threshold of Pain
140dBA – Military Jet takeoff/Gunshot (close range)
160dBA – Instant Perforation of eardrum
When idle, the MSI GTX 660 OC Edition Twin Frozr is basically silent, at the limits of our test equipment. When loaded with a game, the fans spin up from 1,100 rpm to 1,500 rpm, generating around 33.3 dBa of noise. This is also very quiet, barely audible inside an enthusiast chassis.
When primed with the synthetic Furmark benchmark, the fans spin up by another 100 rpm and this increases the noise levels to around 34 dBa.
When factoring in thermal performance with noise emissions, this is a very well balanced fan profile and a good indication that the heatpipe cooler is doing a great job without the need for overactive fan speeds.