x86組合語言
有個cpuid的指令
可配合各大cpu廠商的相關spec進行對照

有cpu型號, cpu序號, cpu內的catch size...等

或是用 CPU-Z 這個軟體去看, 但看不到 cpu序號, 只能看型號
http://www.cpuid.com/softwares/cpu-z/versions-history.html

凡是硬體或比較低階的問題就往API想，你要取得CPU的序號方式可以呼叫kernel32中的GetSystemInfo，GetSystemInfo的參數請參照MSDN網頁說明

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/sysinfo/base/system_info_str.asp

寫法如下(按下Command1按鍵就可以取出CPU號碼)，希望對你有幫助。

Private Declare Sub GetSystemInfo Lib "kernel32" (lpSystemInfo As SYSTEM_INFO)

Private Type SYSTEM_INFO

dwOemID As Long

wProcessorArchitecture As Long

wReserved As Long

dwPageSize As Long

lpMinimumApplicationAddress As Long

lpMaximumApplicationAddress As Long

dwActiveProcessorMask As Long

dwNumberOrfProcessors As Long

dwProcessorType As Long

dwAllocationGranularity As Integer

wProcessLevel As Integer

wProcessorRevision As Integer

End Type

Private Sub Command1_Click()

Dim CPUInfo As SYSTEM_INFO

GetSystemInfo CPUInfo

MsgBox "你的CPU是" & CPUInfo.wReserved

End Sub
可以參考下述網址：
http://www.vbgood.com/vbt.good/vbt.good/t7321.html
也是一個不錯的解決方式