Growth rates of the MHD modes as a function of wave number, for k aligned with the x-axis for an angle θ = 0.3π and δ = π/4. The thermal mode is stable above k_x ≈ 1.20π, which is the critical wave number for these conditions. The growth rate of the fast mode was multiplied by 50 for clarity. The equilibrium temperature is 0.50 MK; the density and magnetic field are the default values.