dvi to hdmi adjust overscan on ati x1300

Hi to everyone, i've just finished my setup for my HTPC.

I'm using my old pc (it's my pc but it's old).

Amd Athlon XP 2400+
1gb ram
400 gb hdd
Ati Radeon 1300
Tv LCD 32"
Audigy 2 ZS
Creative 5.1 Sound System

Windows XP SP2
Cyberlink Power Cinema 5.1 as Media Center (you should try it, works fine on XP, it's pretty, easy to use, and has everything you need)

My problem is the following, i'm connecting my graphic card using the dvi connector to hdmi, but i'm losing 3 cm on the screen caused by the overscan, i've read somewhere (i don't know where) that it exist a tool that helps to adjust that, without using the graphic card control panel.

(i've already used the ati CP, but the only way is to override overscan and i only managed to crop the picture or having black bars)

I would like to adjust the overscan in a way that the picture on the screen fits perfectly (or almost perfectly).

Thanks for reading this, and spending your time replying this post, i apologise for my english i'm used to speak/write in spanish and not in english.

Thanks
Eduardo