  We study the Cauchy problem of three-dimensional compressible non-isentropic
magnetohydrodynamic (MHD) fluids in $\mathbb{R}^3$. Applying delicate energy
estimates, initial layer analysis, and continuation theory, we establish the
global existence and uniqueness of strong solutions, which may be of possibly
large oscillations, provided that the initial data are of small total energy.
In particular, both interior and far field vacuum states are allowed. This
improves our previous work where the initial quantity
$\|\rho_0\|_{L^\infty}+\|H_0\|_{L^3}$ must be small enough and the viscosity
coefficients should satisfy $3\mu>\lambda$. Furthermore, we also derive the
algebraic decay estimates of the solution. To our best knowledge, this is the
first result on time-decay rates of solutions to the Cauchy problem of
multi-dimensional compressible non-isentropic MHD equations with vacuum.
