Vba experts: Need help with date and time stamp being static

[bamaisgreat]

Thanks for looking the code below is what Im currently using. I need to modify this so it does not look in the entire row.
Example: instead of it looking in column 3 and 20 i need to look at column 3 and 20 down to row 25 starting with row 4.

Private Sub Worksheet_Change(ByVal Target As Range)
    If Target.Column = 3 Then
        Application.EnableEvents = False
        Cells(Target.Row, 20).Value = Date + Time
        Application.EnableEvents = True
        End If
        
End Sub

 

[bamaisgreat]

Sorry about that I had two threads and responded incorrect...Thanks for you help I give it a try...