Came across a BSOD issue when running Server 2008 R2 w/ Hyper-V on a Dell Precision T3500. Specifically, there is an issue with the Intel Nhalem-based CPUs (Xeon 5500 series and Core-i series). Specifically the stop error is 0x00000101 with an error o CLOCK_WATCHDOG_TIMEOUT
Microsoft has released this hotfix to address the issue.
Works like a charm!