Excel: Auto Date Stamp

I have an excel spreadsheet that I would like to have cell A1 updated any time a change is made to cells A5:G116. I have played around with mutiple statments but each time I receive and error. In all honesty I am not a skilled VB writer, but I am learning day to day. So far I have:

Private Sub Worksheet_Change(ByVal Target As Range)
If Range(“A5:G116”) Is Nothing Then Exit Sub

What do I need next to return the results to cell A1?