If \( \alpha \), \( \beta \) and \( \gamma \) are the roots of the equation \( 5x^3 - qx - 1 = 0 \), (\( q \in \mathbb{R} \)) then find the value of \( \dfrac{\alpha^2 - 3}{\beta \gamma} + \dfrac{\beta^2 - 3}{\gamma \alpha} + \dfrac{\gamma^2 - 3}{\alpha \beta} \).
