make dropdown winder than column in DataGridView

[Andrus]

I need to make dropdown list wider than column width.
I tried code below but dropdown width is not increased when I open dropdown.
How to increase it ?
using System;
using System.Windows.Forms;

class Form1 : Form {

[STAThread]
static void Main() {
try {
Application.Run(new Form1());
}
catch (Exception e) {
MessageBox.Show(e.ToString());
}
}

private DataGridView dataGridView1 = new DataGridView();

public Form1() {
Controls.Add(this.dataGridView1);
Load += new EventHandler(Form1_Load);
}

private void Form1_Load(object sender, EventArgs e) {
DataGridViewComboBoxColumn
col = new DataGridViewComboBoxColumn();
col.DropDownWidth *= 3;
dataGridView1.Columns.Add(col);
}
}