There is another way to boost sound in both Windows Vista & 7 by adjusting Speakers' properties
1. Click right at Speakers' icon at Windows' taskbar.
2. Select Playback Devices.
3. Select Speakers.
4. Click Properties -> Enhancements -> select "Loudness Equalization"
5. Click OK
I've done it in my Macbook Pro 13" 2009 with Windows 7.
It works for me hopefully, it'll work to you too.
1. Click right at Speakers' icon at Windows' taskbar.
2. Select Playback Devices.
3. Select Speakers.
4. Click Properties -> Enhancements -> select "Loudness Equalization"
5. Click OK
I've done it in my Macbook Pro 13" 2009 with Windows 7.
It works for me hopefully, it'll work to you too.