Ultra-silent: Global Win CAK - II 58
If you're looking for an ultra-silent copper CPU cooler, then look no further than the CAK-II 58. Its five-millimeter thick base plate and almost forty 0.5-millimeter thick ribs are quick to absorb heat from the processor. The slowly turning fan prevents the warmth from building up in the cooler. Its noise level of 40dB(A) is hardly perceptible.
The surfaces of the cooler are impeccable. The only clouds to this silver lining are the somewhat wobbly rivets that hold the housing and the base plate together. Other manufacturers connect the two with small screws. The cooling capacity is more than enough for an Athlon XP 2000+ or an Athlon 1400 Thunderbird.
The CAK-II58 is an excellent compromise between acceptable cooling and a low noise level.