Solved ATI Radeon UNDER/OVER SCAN Problem

Identifying the Problem

Ever since I connected my PC(with an ATI Radeon GPU) with an HDTV, I was getting these black borders around the screen,i.e., the picture never seemed to reach the edge of the screen. After a few Google searches, I found that ATI graphics card when connected to a HDTV, were more prone to show this problem.It happens because of a thing called Overscan.

I never installed the Catalyst Control Center(CCC). My HDTV was connected through a HDMI cable and it worked fine (albeit with borders) and for some reason, installing the ATI Drivers showed errors on my PC.

I hate disclaimers, but...

"DO THIS AT YOUR OWN RISK.Some solutions listed here involve tinkering with the 'Registry' of your Windows PC. And the Registry is serious stuff. Very serious. If you are not careful, you might have to REINSTALL Windows and you might lose your data." 

Possible Solutions

Before you try anything with your PC's registry, scroll down and read "Tweaking the TV" because the problem may not be PC related. 

I found a few solutions from the various articles I read, which are listed below. 

1. Through CCC: Under the "desktop and display" tab, right click on your main display and select "configure", you will see a "Scaling Options" Tab. Here set the Overcan to 0%. I didn't follow this because, some users reported that the problem returned when they restarted or set another resolution or started playing a game, in which case, the game changes the resolution as per the settings. Then the users had to set settings for each particular resolution and refresh rate.
2.  Through Registry: Changing some REG D_WORD values in the Registry.
   (HKEY_LOCAL_MACHINE\\SYSTEM\\CurrentControlSet\\Control\\Video\\). I used this because, I can set the registry values for once and not be bothered by the settings again.

My solution

I followed the 2nd one along with a small tweak with the TV itself. Because sometimes the problem may not be related to your GPU, but actually related to your TV. Again, please see "Tweaking the TV" part of this post, for settings on your TV. The steps listed below may look very difficult, but it's very easy. Look at the pictures and fire away any doubts in the comments. Let's begin...

1. Open Registry Editor: Tap the Start button and type "regedit" and hit Enter.
2. Go to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Video\
               

   

   HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Video\

3. There will be some keys under "Video" named like this {XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX} but with different numbers and letters.
4. Rightclick on the Video key at the top of the tree and "Find" the resolution, that you want to change (e.g. 1920x1080,1440x900). 
5. The keys which you will need are named this way DALR6 DFPXXXXxYYYYx0xFF, where
   XXXX= Horizontal Resolution
   YYYY= Vertical Resolution
   FF= Frequency 
6. WARNING!! - Take a backup of the original keys before you continue. Right-click {XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX}-type key and click "Export".
7. Right-Click on the key matching the screen resolution and frequency you want to remove the borders of and select "Modify".
                              

   

   Right-Click and select "Modify"

8. The window that opens next will show you bunch of "00" but also some non-zero bunches (like "04" "08"). Change all of these non-zero bunches to "00".
                                    

   

   Change all of these non-zero bunches to "00"

9. Exit from "Registry Editor". Don't poke around in "Registry Editor" because it WILL bite you and your computer.
10. The effects will take place when you set your display resolution to the one you changed in the Registry.

Tweaking the TV

This tweaking was necessary because, when I followed the steps given above, some parts of my screen were cut off, like my Taskbar did not have the Start button anymore. If this happens to you, follow the steps given below. This tweaking is for Samsung HDTVs. But, of course you are free to try it on TVs of other brands.

1. Hit the "Source" button on the TV's remote. 
2. Rename the source to "PC" or "DVI PC" by using the "Tools" button.

 Hope this post helped you to solve your problem.