975530 – Last Review: August 10, 2010 – Revision: 14.0
Stop error message on a Windows Server 2008 R2-based computer that has the Hyper-V role installed and that uses one or more Intel CPUs that are code-named Nehalem: “0x00000101 – CLOCK_WATCHDOG_TIMEOUT”

I have a newly installed HP DL380G6 , completely up to date etc.. that has been randomly rebooting. I installed who crashed to review the memory dump and found that each time it happened this error code was generated CLOCK_WATCHDOG_TIMEOUT

So after some research on the web I found A Hot Fix available from Microsoft to fix the problem. You can get it HERE