Comparison of the planetary radii (top), Ohmic efficiency (middle), and background magnetic field at the surface B_atm (bottom) between models with a fixed (solid lines) and varying (dashed) T_eq. We consider models with T_eq = 1500 K (black and blue lines with v_avg = 0 and 1000 m/s, respectively) and 2000 K (grey and red lines with v_avg = 0 and 178 m/s, respectively), where these values of T_eq are at t = 5 Gyr in the cases with evolving stellar luminosity.