Six pin power connector, the card uses more than 75 Watts, your PCIe bus can't deliver that and therefore the cards feeds of the PSU directly.

The four copper heatpipes that bind together to the GPU block. Arctic Cooling actually pre-applies their MX-2 thermal compound to the base of all their heatsinks — it's a fairly good product.

When you look closely at the the cooler you'll see the pipes and aluminum cooling ribbons. An internal coolant is inside these pipes (air/gas/fluid/whatever floats the boat) and flows from the GPU chamber towards the cooling ribbons where heat will be dissipated with the help of airflow. The cooling method is all based around circulation. Although we just named it gas, the coolant can be something else or actually change into a gas. Usually it is liquid when cold, but easily becomes a vapor when heated and vice versa. As heat is absorbed from the processor (GPU), it will follow the path of least resistance to the aluminum fins, where the heat then dissipates.

I believe passive cooling for this unit won't cut it unless you have exceptional cooling/airflow in your PC. therefore please install the dual fans that are supplied.

Here we can see them installed.

Small subtleties ... the RAM chips are covered with little heatsinks as well.