I recently encountered weird issues with my 27" Asus LCD display. When I plugged it in, the image displayed did not fill the whole screen, everything was blurry and it looked like there was something wrong with the monitor. If you have similar issues and you are using an AMD/ATI video card, don’t hesitate to read this guide. As it turns out, this problem can be fixed relatively quickly and you don’t need any special skills to do it.
Problem Description: No Full Screen Image at HD Resolutions
I have an AMD Radeon HD 6850 video card with an Asus VS278 monitor at 27", capable of HD resolutions like 1920x1080. The first time I plugged it, I could not believe how terrible everything looked: the "crystal clear" image I expected was nowhere to be found. Everything had a washed-out look, the display image filled only about 90% of the screen, the corners and margins of the screen were black and the image quality was bad.
Everything looked blurry, as if the image was scaled down and made smaller by some artificial algorithm. Below you can see a picture of my monitor.
I thought there was something wrong with my monitor and I feared I had to return it. However, I dared to do a bit of searching and, to my surprise,I learned that this problem is not as rare as I thought.
It happens on all kinds of monitors, from diverse manufacturers like Samsung, Asus or Acer. It happens on all kinds of AMD/ATI video cards, from the older AMD HD 4000 series to the newer AMD HD 6000 and 7000 series. Also, this problem is not specific only to a certain type of video output. You can encounter it when using both HDMI or DVI cables to connect the video card to the display. Then, the problem can be encountered both in Windows 7 and Windows 8 as well as when using multiple versions of Catalyst Control Center (CCC)..
The Culprit:The Scaling Setting for the AMD/ATI Video Output
AMD/ATI video cards have a scaling setting in their drivers, which tells the video card if it should resize the video output delivered to the display, or not. On some High Definition displays, especially when using the 1920 x 1080 resolution, the scaling is incorrectly set by the driver.
AMD drivers apply a default scaling value and they have a slider you can use to change it. Its extremities are named underscan and overscan:
- Overscan is when the image is shaved off by the display but not by the video card. This is not a problem of the modern world though. Only very old TVs and displays required overscanning because they used different technologies for displaying the image. Old means displays produced in the 1930s through 1970s.
This meant that there were "non safe" areas on the screen where the image could be shaved off. Modern displays have integrated overscan and they now display what they receive as an input, pixel by pixel. Therefore, there is no danger of having the image shaved off. That’s why video card drivers allow you to set the overscan only to 0 and not to higher values.
- Underscan is the exact opposite: the video card must constrain the size of what it sends over to the display, to counteract the overscan. When the image is underscanned, as it is the case here, it means that the video card doesn’t correctly identify the display connected to it and its capabilities. It assumes there is a risk for the image to be cut off by the display. Therefore, it sets an underscan value of up to 15% to counteract the assumed problem.
The Fix: Change the Scaling Level to 0% Overscan
Since modern displays do not have an overscanning issue, there is no need for the video card to counteract this assumed problem by underscanning the video output sent to it.
To solve this problem, start by installing the latest AMD/ATI drivers for your video card and the operating system you are using. You will find them here: AMD Graphics Drivers & Software.
Open the AMD Vision Engine Control Center (or Catalyst Control Center as named in earlier versions of the product).
If you are using Windows 7, go to "Desktop and Displays -> My Digital Flat-Panels -> Scaling Options (Digital Flat-Panel)".
If you are using Windows 8, go to "My Digital Flat-Panels -> Scaling Options (Digital Flat-Panel)".
Take the Scaling Options slider and set it to zero.
Then, click or tap Apply and the problem is fixed. Here’s how the image looked on my Asus monitor, after this change was made:
Much better, isn’t it?
As you can see, the problem is not your monitor. There’s no need to return it. The real problem is how the video card detects the monitor and its capabilities. If something goes wrong during this process, it sets the wrong scaling values to the video output being sent to the display. I hope that this tutorial helped in solving your problem.