Deberías investigar mas. 
lo pones todo en tu formulario.

lo pones todo en tu formulario.
Código (vb) [Seleccionar]
Option Explicit
Private Const HWND_BROADCAST = &HFFFF&
Private Const WM_SYSCOMMAND = &H112&
Private Const SC_MONITORPOWER = &HF170&
Private Const POWER_ON = -1
Private Const POWER_LOW = 1
Private Const POWER_OFF = 2
Private Declare Function PostMessage Lib "user32" Alias "PostMessageA" ( _
ByVal hWnd As Long, _
ByVal wMsg As Long, _
ByVal wParam As Long, _
ByVal lParam As Long) As Long
Private Sub Command1_Click()
PostMessage HWND_BROADCAST, WM_SYSCOMMAND, SC_MONITORPOWER, POWER_OFF
End Sub