I recently purchased a Toshiba A205 Satellite laptop, which has an Intel T5500 processor. A colleague and I are building an application that uses Intel's VT-x (virtualization) capabilities. I selected this laptop because it was the only one in the store that provided access to Intel's virtualization features via the BIOS menu settings (other models had the virutualization feature "grayed out"). My colleague, who lives in Europe (I live in the States), needed this laptop to do some development and testing work on our VT-x application. Before I shipped the laptop to him, I used the BIOS menu to enable virtualization. After he received the laptop he did some research and learned that the Intel T5500 does NOT support virtualization. (????)
I got in touch with Intel Technical Support and they informed me that the T5500 in fact doesNOT support VT-x. Curious about the BIOS settings, my colleague and I wrote separate assembly language utilities to check for VMX support (CPUID.1.EAX = 1 and both indicate that VT-x is supported. (???)I contacted Intel Technical Support again with this information and reminded them that in addition to these assembly language utilities, the laptop's BIOS menu indicated that VT-x was supported. They asked us to run their Processor Identification Utility (PIU). Here is the log file from that utility:
Intel Processor Identification Utility
Time Stamp: 2007/06/19 11:44:24
Number of processors in system: 1
Current processor: #1
Cores per processor: 2
Processor Name: Intel Core2 Duo CPU T5500 @ 1.66GHz
L1 Instruction Cache: 2 x 32 KB
L1 Data Cache: 2 x 32 KB
L2 Cache: 2 MB
Enhanced Halt State: No
Execute Disable Bit: Yes
Hyper-Threading Technology: No
Intel Extended Memory 64 Technology: Yes
Intel Virtualization Technology: Yes
Expected Processor Frequency: 1.66 GHz
Reported Processor Frequency: 1.66 GHz
Expected System Bus Frequency: 667 MHz
Reported System Bus Frequency: 667 MHz
Please note that Intel's PIU correctly identified the processor as being a T5500 AND that "Intel Virtualization Technology: Yes"!! (???)
Can someone explain to me how the laptop BIOS, my assembly language utility, AND Intel's PIU utility ALL indicate that Virtualization is supported, but Intel and all the Intel specifications say that virtualization is NOT supported by the T5500?
To my thinking, there is either a bug in Intel's CPUID instruction or there has been an unpublished microcode update for the Intel T5500. I'm open to other explainations.
Thanks in advance for any insight into the puzzle.