We　report　on　a　high-power　960-fs　subpicosecond　pulse　generation　from　a　passively　mode-locked　ytterbium-doped　large-mode-area　photonic　crystal　fiber　oscillator　in　the　all-normal　dispersion　regime.　Stable　and　self-starting　operation　is　obtained　by　exploiting　an　efficient　combination　of　a　high　modulation　depth　semiconductor　saturable　absorber　mirror　and　the　nonlinear　polarization　evolution　mode-locking　mechanism.　In　the　single-pulse　regime,　the　laser　directly　generates　the　output　power　of　3.15　W　at　the　repetition　rate　of　83.7　MHz,　corresponding　to　the　pulse　energy　of　37　nJ.　The　center　wavelength　is　1,030　nm　with　the　spectral　bandwidth　of　8　nm　at　the　maximum　output　power.　The　output　characteristics　of　the　oscillator　are　discussed　carefully.