static extern int NtSetTimerResolution(int DesiredResolution, bool SetResolution, out int CurrentResolution );

Declare Function NtSetTimerResolution Lib "ntdll.dll" (ByVal DesiredResolution as UInteger, ByVal SetResolution as Boolean, ByRef CurrentResolution as UInteger)

NtSetTimerResolution(0.5, True, 0)