  We present a lattice study of the phase transitions at zero and nonzero
temperature for the $SU(3)$ gauge theory with a varying number of flavours
$N_f$ in the fundamental representation of the gauge group. We show that all
results are consistent with a lower edge of the conformal window between
$N_f=8$ and $N_f=6$. A lower edge in this interval is in remarkable agreement
with perturbation theory and recent large-$N$ arguments. .
