用WMI来查询CPU的频率，一直没问题：

"Select MaxClockSpeed From Win32_Processor Where ProcessorType = 3"

结果今天在一台虚拟机上发现无法查询了，于是乎在Powershell里查询了一下

Get-WmiObject –Class Win32_Processor

看看，ProcessorType是空的，Σ( ° △ °|||)︴

坑爹啊，VMWare创建的就没问题，ProcessorType是3.

ProcessorType

Data type: uint16

Access type: Read-only

Primary function of the processor.

Value Meaning

1 (0x1) Other

2 (0x2) Unknown

3 (0x3) Central Processor

4 (0x4) Math Processor

5 (0x5) DSP Processor

6 (0x6) Video Processor

参考资料：

http://msdn.microsoft.com/en-us/library/aa394373(v=vs.85).aspx

VirtualBox创建VM结果ProcessorType是空的