The moment of inertia of a uniform thin rod about a perpendicular axis passing through one end is \( I_{1} \). The same rod is bent into a ring and its moment of inertia about a diameter is \( I_{2} \). If \( \frac{I_{1}}{I_{2}} \) is \( \frac{x \pi^{2}}{3} \), then the value of \( x \) will be ______.