Efficient cw intracavity frequency doubling of a diode end-pumped $\mathrm{Nd}\text{:}\mathrm{Gd}{\mathrm{VO}}_4$ laser that operates in the ${}^4{\mathrm{F}}_{3/2}\to {}^4{\mathrm{I}}_{9/2}$ transition at $912\mathrm{nm}$ is demonstrated. A $15\mathrm{mm}$ long lithium borate crystal, cut for critical type I phase matching at room temperature, was used for second harmonic generation of the fundamental laser. A maximum output power of $14.8\mathrm{W}$ in the deep blue spectral range at $456\mathrm{nm}$ was achieved at an incident pump power of $40\mathrm{W}$ . In 2 h we achieved an optical-to-optical conversion efficiency of 37% with a better than 2.57% power stability.