最近我的 27" Asus LCD 显示器(Asus LCD display)遇到了奇怪的问题。当我插入它时，显示的图像并没有填满整个屏幕，一切都很模糊，看起来显示器有问题。如果你有类似的问题和如果您使用的是AMD/ATI video显卡，请不要犹豫阅读本指南。事实证明，这个问题可以相对快速地解决，您不需要任何特殊技能即可。
问题描述：(Problem Description)高清分辨率(HD Resolutions)下没有全屏图像(Full Screen Image)
我有一个AMD Radeon HD 6850 视频卡(video card)和一个27 英寸的华硕 VS278 显示器(Asus VS278 monitor)，能够达到 1920x1080 等高清分辨率。我第一次插入它时，我无法相信一切看起来多么糟糕：我期望的“水晶般清晰”的图像是无处可寻。一切都显得苍白，显示图像(display image)仅占屏幕的90％左右，屏幕的角落和边缘是黑色的，图像质量(image quality)很差。
一切看起来都很模糊，好像图像被某种人工算法缩小并变小了。下面你可以看到我的显示器的图片。
我认为我的显示器有问题，我担心我不得不退回它。但是，我敢于进行一些搜索，令我惊讶的是，我发现这个问题并不像我想象的那么罕见。
它发生在来自三星(Samsung)、华硕或宏碁(Asus or Acer)等不同制造商的各种显示器上。它发生在各种AMD/ATI video卡上，从较旧的AMD HD 4000系列到较新的AMD HD 6000和 7000 系列。此外，此问题不仅仅针对特定类型的视频输出(video output)。使用HDMI 或 DVI 电缆(HDMI or DVI cables)将视频卡(video card)连接到显示器时，您可能会遇到这种情况。然后，在Windows 7和Windows 8以及使用多个版本的Catalyst Control Center ( CCC ) 时都可能遇到此问题。
罪魁祸首：AMD/ATI Video Output的缩放设置(Scaling Setting)
AMD/ATI video在其驱动程序中有一个缩放设置，它告诉显卡(video card)是否应该调整传送到显示器的视频输出的大小。(video output)在某些高清(Definition)显示器上，尤其是在使用 1920 x 1080分辨率时，驱动程序错误地设置了缩放比例。
AMD驱动程序应用默认缩放值，并且它们有一个滑块，您可以使用它来更改它。它的末端被命名为underscan和overscan：
修复(Fix)：将缩放级别更改为0(Scaling Level) % 过扫描
由于现代显示器没有过扫描问题，因此视频卡(video card)无需通过欠扫描发送给它的视频输出(video output)来解决这个假设的问题。
要解决此问题，请首先为您的视频卡(video card)和您使用的操作系统(operating system)安装最新的 AMD/ATI 驱动程序。您可以在这里找到它们：AMD 显卡驱动程序和软件(AMD Graphics Drivers & Software)。
打开AMD Vision Engine Control Center（或产品早期版本中命名的Catalyst Control Center ）。
如果您使用的是 Windows 7，请转到"Desktop and Displays -> My Digital Flat-Panels -> Scaling Options (Digital Flat-Panel)"。
如果您使用的是 Windows 8，请转到"My Digital Flat-Panels -> Scaling Options (Digital Flat-Panel)"。
使用Scaling Options滑块并将其设置为零。
然后，单击或点击应用(Apply)，问题就解决了。这是进行此更改后图像在我的华硕显示器上的外观：(Asus monitor)
好多了，不是吗？
结论
如您所见，问题不在于您的显示器。没有必要退货。真正的问题是视频卡(video card)如何检测显示器及其功能。如果在此过程中出现问题，它会将错误的缩放值设置为发送到显示器的视频输出。(video output)我希望本教程有助于解决您的问题。
Fix HD Monitors and AMD/ATI Cards Not Displaying a Full Screen Image
I recently encountered weird issues with my 27" Asus LСD diѕplay. When I plugged it in, the image disрlayed did not fill the whole screen, everything was blurry and it lookеd like there was something wrong with thе monitor. If you have ѕimilar issues and you are using an AMD/ATI video card, don't hesitate to read this guide. As it turns out, this рrоblem can be fixed relatively quickly and you don't need any special ѕkills 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?
Conclusion
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.
