Why not just type the capitals? A lot less mucking around than using macros or formulae!
As for the macro, you could use:
Code:
Private Sub Worksheet_Change(ByVal Target As Excel.Range)
If Intersect(Target, Range("A8")) Is Nothing Then
If Intersect(Target, Range("A10")) Is Nothing Then Exit Sub
End If
Target.Value = WorksheetFunction.Proper(Target.Text)
End Sub