I have Mac Pro 3,1.
I have just bought 2x Xeon E5450 SLBBM E0 stepping and found that there are unsupported by my Mac Pro.
I tried to google for this problem and found that only SLANQ C0 stepping works with it.
SLANQ has CPUID 10676;
SLBBM has CPUID 1067A
The MacPro 3,1 firmware has the microcode for the SLANQ (CPUID 10676).
Is it possible to edit MacPro 3,1 firmware and add support of SLBBM (CPUID 1067A)?