I have a new Compaq desktop to which I have added an ATI Radeon X1050 PCI Express video card.
It is hooked up over the DVI to my Panasonic 42" plasma.

I have set the resolution to fill the screen, however I can't see the edges of the screen on the TV. For example, I can only see the top 1/3 of the taskbar and can't see any of the minimize, maximize, and close icons in the upper right so corner.

Is there any software which will allow me to adjust the output from the video cards so as to shrink the screen?

On a related note, the computer will not boot unless I have a monitor plugged into the VGA port on the card. does anyone know what is causing this or how to work around having a second monitor by my TV?

Thanks.

It doesn't sound like you are sending the proper resolution from the card to the plasma. You need to work on that -- it's not a 'software adjustment issue.'

I have never heard of a PC needing any monitor plugged into it in order to boot up, much less a VGA requirement. However, since you say that you added the ATI card, look into disabling the PC's integrated graphics (I bet it has that) via the hardware devices list. Then try a reboot.

You will need to check your plasma monitor manual on the supported resolutions. For best results you will want to choose a 16:9 resolution, rather then a 4:3 resolution.

Got the resolution issue solve, however it still does not boot unless there is a monitor plugged in on the VGA. It does not even reach the Windows welcome screen because when I push the power button, the computer immediately powers down instead of going through the full shutdown.
This is a totally new problem I have never encountered (I used to work in PC repair) and am out of ideas. The onboard card is disabled in the bios.
Thanks again.

Its called "headless booting" and its generally controllable in the bios or firmware for the graphics card. The intel mac minis have a bit of a fit without a monitor (when using an OS other than OS X) and its just a matter of changing an EFT setting.

With your rig it sounds like you might consider searching the forums or support site for the graphics card.

Does the monitor have shrink/expand controls? If it does, have you tried them? Maybe it's just trying to display the missing stuff past the edges.

This is called 'overscan'.

You will notice that on computer monitors that there is usually a small black border aroudn the edge of the screen. When watching TV, there is no black border, as it isn't considered acceptable on a television.

To ensure this does not occur, televisions never show the entire picture. There is always a tiny tiny part of the picture that is off the edge. You have never noticed it until you hooked up a computer.

You will need to reduce the overscan. Luckily, you have an ATI graphics card. In the ATI control panel there usually is an HDTV tab (or section) that will let you reduce you resolution in non standard increments.

For instance, instead of running 1280x720, it is adjusted to 1268x712 (or something like that, I'm not in front of that PC right now).

This link explains overscan. Ignore the pricey hardware solutions as you shouldn't need it with the ATI card.
http://www.highdefinitionblog.com/?page_id=127

EDIT: saw you fixed the problem. I'll leave the post here for others.