What am I seeing?
For systems with an Intel® Xeon® Processor 5600 Series with Windows* Server 2008, you need to install the Microsoft* hotfix KB 981791 before installing Hyper-V.
Why am I seeing it?
The Intel® Xeon® Processor 5600 Series has a new caching feature that was not introduced until after Windows* Server 2008 SP2, which may cause BSOD on systems without the hotfix installed.
How to fix it
"STOP: 0x0000001a" error message on a computer that has an Intel Westmere processor together with the Hyper-V role installed on Windows Server 2008 or on Windows Server 2008 R2