A very interesting article if you use AMD processors in your DC's
A Windows Server 2003-based server may experience time-stamp counter drift if the server uses dual-core AMD Opteron processors or multiprocessor AMD Opteron processors. When this problem occurs, operations that rely on the time-stamp counter may not function correctly. These operations include network communications and performance monitoring. For example, if the server is an Active Directory domain controller, you may receive the following error message:
Unexpected Network Error (Event ID 1054)
Event Description:
Windows cannot obtain the domain controller name for your computer network. (An unexpected network error occurred.) Group Policy processing aborted.
http://support.microsoft.com/default.aspx/kb/938448