Since PowerColor had exclusive use of S1 for their X1950 Pro Silence Edition that we wrote about here, Arctic Cooling released Accelero S2, the little brother of this very efficient passive cooler.
Unlike S1 that has four, S2 is cut down to only two heatpipes, that is enough to keep mid-range graphic cards cool. You should use this one with cards such as Radeon x1650 or Geforce 7600. According to Arctic Cooling the cooler does a better job then stock X1650XT cooler and its completely silent.
Thirty one of optimised heat sink fins are designed to allow air flow to pass easily through so the heat could be removed more effectively. AC bundles RAM heat sinks with S2.
Accelero S2 is compatible with ATI (Radeon X1650, X1600, X1550, X1300, X1050, X850, X800, X700, X600, X550, X300 and 9XXX series) and nVIDIA (GeForce 7600, 7300, 6600, FX 5950, FX 5900, FX 5700 (Ultra), FX 5600, FX 5500, FX 5200, 4 TI and MX series) graphic cards. The suggested retail price is USD 22, and for Europe EUR 18.
You can find more information on Arctic Cooling.