CPU ID using C++ - windows

c, c++, windows

Solution

Do you mean "serial number", "who made the processor", or the "string that identifies the make and model of the processor".

Serial number:

Unless you have a Pentium III, you do not have a "unique ID" associated with your CPU.

Intel introduced the unique id (serial number) instruction with the P3. But after a huge uproar over privacy, they quickly disabled that feature in subsequent CPU releases.

For the record, the instruction that executed this feature in assembly:

mov eax, 3
cpuid

The processor serial number was the concatenation of eax, edx, and ecx together

You can achieve the same thing with __cpuid function by passing "3" as the second parameter. But it won't work or return a serial number unless you have a P3.

Vendor (who made the processor)

int regs[4] = {0};
char vendor[13];
__cpuid(regs, 0);              // mov eax,0; cpuid
memcpy(vendor, &regs[1], 4);   // copy EBX
memcpy(vendor+4, &regs[3], 4); // copy EDX
memcpy(vendor+8, &regs[2], 4); // copy ECX
vendor[12] = '\0';
print("My CPU is a %s\n", vendor);

In your case, this should print "GenuineIntel".

Make and Model (BRAND String)

If you want all the details of the CPUID instruction, including on how to get the make, model, and stepping of your CPU, as well as the "Brand String" such as "Intel(R) Core (TM)i7-3770 CPU @ 3.4GHZ...." you can reference the Intel manual at the link below. Scroll down the document to find the docs for CPUID. I'm too lazy to type it up for you.

http://www.intel.com/content/dam/www/public/us/en/documents/manuals/64-ia-32-architectures-software-developer-vol-2a-manual.pdf

The __cpuid() instruction provided by the MSVC compiler maps "InfoType" to EAX before the call to the cpuid instruction. After that instruction returns, EAX, EBX, ECX, and EDX get copied to the CPUInfo[4] array you passed into this function.

Problem

Original source