Snip: Put the card back in your system, plug the adapter into a 4 pin molex, and plug the fan in. The white connectors are low speed, the black ones are high speed. From my experience with the VF-700CU, low speed will offer plenty of cooling. At low speed, the fan is virtually silent. At high speed, the fan is pretty audible, but nowhere near as loud as say, an 80mm case fan running at a full 12V.
Full review @ OCIA