Stock AMD Athlon/Sempron cooler noise level in dB?

[homestarmy]

I have the stock cooler for a Palermo Sempron 3000+. It is pretty quiet, but I was just curious how many dB it is rated at, or what any of the current ones for Athlons, etc are rated at.

For reference, the box on my Arctic Cooling Silencer says that the stock cooler for the Athlon 64 3200+ is 2.6 Sones, but I can't figure out how to convert it.

 

[furballi]

50 phons = as loud as 50dB at 1000Hz test tone.

50 phons = 2 sones
60 phons = 4 sones

2.6 sones is approximately 56dB at 1000Hz test tone.

A quiet Zalman 7700Cu running at 970 rpm puts out about 24 dBA at one meter.

 

[homestarmy]

Well there's no way that the stock AMD cooler is 56dB though...

...unless they're just lying.