I just received my brand spanking new W520 Thinkpad and I'm concerned because if you run CPU-Z or you open a cmd window and type in "wmic idecontroller get deviceid" you would expect to see if your W520 board is B2 stepping or B3 stepping. If REV_04 is displayed through either of these methods would this indicate a B2 (buggy hardware) stepping whereas a revision 5 is a newer stepping without the bugs?
Can Lenovo explain these unexpected reporting results?
While some B2 level preproduction ThinkPads may exist as part of pre-release testing and may have be provided to select large accounts for early evaluation and development of standardized images, no production level ThinkPads have been built and shipped with B2 level chips. The erroneous results returned by some software tools is related to Lenovo's implementation of CRID. Lenovo's engineering team explains:
"Lenovo has not shipped B2 Sandy Bridge silicon on production ThinkPad systems. The ID being referenced returns the Intel CRID -- Compatibility Revision ID -- of the chip, not the actual chipset revision. This is a feature implemented by Intel and Lenovo on recent ThinkPad notebooks which, in order to maintain image stability required by many Large Enterprise customers, hides a chip revision change from the Operating System, such as Microsoft Windows to keep it from re-installing device drivers when it detects a revision ID change. This is a web page which describes Intel Stable Image Platform Program --http://www.intel.com/itcenter/topics/refresh/sipp.
You can use the ME Info program Intel provides for use with their Management Engine.
Here is an example of of the returned results:
PCH ID got revised after version 7.1.13.1088 onwards.
Version 7.1.14.1107
Version 7.1.13.1088