A rubidium-vapor laser pumped by a pulsed titanium sapphire laser was presented to investigate the dynamics of diode-pumped rubidium-vapor lasers. The vapor cell was filled with 70 kPa methane and 6 atm He at room temperature. The laser generated an average power of 208 mW, according to the conversion efficiency of 19 % from absorbed 779.8 nm pump light to 795 nm laser. High peak power of 693 W rubidium-vapor laser was achieved with a 100 ns (FWHM) pulse width at a repetition rate of 3 kHz. Our experiments illustrate that the reabsorption of the Rb-He-CH4 mixtures will be a significant limitation in DPALs with the high pump power intensity. It can be deduced that the pump power intensity threshold of the Rb-He-CH4 system (6 atm He, 70 kPa CH4 at room temperature) at 418 K should be >200.6 kW/cm2 if LDs with a linewidth of 0.9 nm are adopted as the pump source.