The temperature dependence of the narrow-band-noise (NBN) intensity and the nonlinear conductivity (NLC) we have observed in NbSe3 implies that a thermal activation process is important in the NBN and NLC for the charge density wave forming below 144 K. The activation energies observed (-2800 K for both the NBN and the NLC) at temperatures below 110 K are of similar magnitude. A field dependence at low fields may be responsible for the discrete discrepancy. The existence of a significant thermally activated contribution to the NLC and NBN, is in serious discord with existing theoretical models of either phenomenon.