[WMI] permissions for Win32_PerfFormattedData_*

Note: if you're trying to use WMI to query any of the performance counters, you don't just need the normal WMI permissions; you also need the account running the query to be added to "Performance Monitor Users" (or, if using a GPO, "BUILTIN\Performance Monitor Users").  In my case, when I ran the query I'd get nothing.  No errors, no data, nothing.  Adding that group (in addition to all the others like WMI perms) fixed it.

in this case, found it (and more) at: http://vniklas.djungeln.se/2012/08/22/set-up-non-admin-account-to-access-wmi-and-performance-data-remotely-with-powershell/