\[ \boxed { {x}^{3}{\frac {\rm d}{{\rm d}x}}y \left ( x \right ) - \left ( y \left ( x \right ) \right ) ^{2}-{x}^{4}=0} \]
Mathematica: cpu = 0.022003 (sec), leaf count = 43 \[ \left \{\left \{y(x)\to -\frac {x^3 \left (-\frac {c_1}{x^2}+\frac {1}{x^2}-\frac {\log (x)}{x^2}\right )}{\frac {c_1}{x}+\frac {\log (x)}{x}}\right \}\right \} \]
Maple: cpu = 0.016 (sec), leaf count = 23 \[ \left \{ y \left ( x \right ) ={\frac {{x}^{2} \left ( \ln \left ( x \right ) -{\it \_C1}-1 \right ) }{\ln \left ( x \right ) -{\it \_C1}}} \right \} \]