What exactly do you mean by the power needle? What heli are you flying?
The collective is just that – it adjusts the main rotor blades’ pitch collectively, i.e. simultaneously and synchronously. When the MR pitch is increased, the power demand is increased, too. This is anticipated by the rotor governor.
The purpose of the governor is to keep the main rotor RPM constant. It does that by adjusting the engine power output via throttle control. The power output is normally monitored using the torque indication.
The required torque depends on many factors including the main rotor pitch, but also the helicopter airspeed and height above the ground. When hovering near the ground (about 1/2 of the main rotor diameter or less), the helicopter experiences the ground effect: the rotor tip vortices are reduced which affects airflow patters around the blades reducing the rotor induced drag. This results in lower power requirement when hovering in ground effect as compared to hovering out of it.