The CPUID opcode is a processor supplementary instruction (its name derived from CPU IDentification) for the x86 architecture allowing software to discover details of the processor. It was introduced by Intel in 1993 when it introduced the Pentium and SL-enhanced 486 processors.
By using the CPUID opcode, software can determine processor type and the presence of features (like MMX/SSE). The CPUID opcode is 0Fh, A2h (as two bytes, or A20Fh as a single word) and the value in the EAX register, and in some cases the ECX register, specifies what information to return.
To install a Hackintosh or other OS on the unsupported platform, such as Intel Pentium G4560. You have to fake a CPUID cheating the system. There have a very easy way to change the CPUID in Virtual Machine.
- Use editor (e.g. notepad) open virtual machine configure file (.vmx)
- Adding following lines:
cpuid.1.eax = "00000000000000110100011010101001" cpuid.1.edx = "10111111111010111111101111111011"
- If CPUID is still not change or invalid, try adding:
cpuid.1.ebx = "00000000000000110100011010101001" cpuid.1.ecx = "10111111111010111111101111111011"
- Save configure file and start your Virtual Machine.
ORACLE VIRTUAL BOX
- Open Command Prompt and switch to VirtualBox working directory.
- Run following command to change CPUID.
vboxmanage modifyvm --cpuidset 1 000306a9 00100800 3d9ae3bf bfebfbff
- Start your Virtual Machine.
Version Information: Type, Family, Model, and Stepping ID (see Figure 3-5)
Bits 07-00: Brand Index Bits 15-08: CLFLUSH line size (Value ∗ 8 = cache line size in bytes) Bits 23-16: Maximum number of addressable IDs for logical processors in this physical package*. Bits 31-24: Initial APIC ID
Feature Information (see Figure 3-6 and Table 3-20)
Feature Information (see Figure 3-7 and Table 3-21)
For more about CPUID information please read this article.