To solve for \( X \) in the equation \( 2X = -4 \), we can divide both sides by 2:
\[ X = \frac{-4}{2} = -2 \]
Now, we need to find the value of \( 8X \). We can do this by multiplying \( X \) by 8:
\[ 8X = 8 \times (-2) = -16 \]
Thus, the value of \( 8X \) is \(\boxed{-16}\).