Format of Pentium Pro microcode update block:
Offset	Size	Description	)
 00h	DWORD	update header version number (currently 00000001h)
		FFFFFFFFh = unused block
 04h	DWORD	revision number of this microcode update
 08h	DWORD	update creation date, as BCD mmddyyyy (month,day,year)
 0Ch	DWORD	family/model/stepping of processor to which update applied
		(same value as returned by CPUID instruction)
 10h	DWORD	checksum (used to force sum of all 512 DWORDs of the update
		block to 00000000h)
 14h	DWORD	revision number of loader needed to install update
		(currently 00000001h)
 18h 24 BYTEs	reserved for future expansion
 30h 2000 BYTEs	encrypted microcode data
SeeAlso: MSR 00000079h,OPCODE "CPUID"