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I have serached this forum and found a few mentions of the issues with 1080p resolution with a pc hooked up. It cuts off the taskbar and the left side of windows. What is the fix for this?? I haven't seen anything real definitive...is the fix with your video card or with the TV?? Thanks in advance.
 

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The TV is overscanning the content you are sending in order to emulate a standard CRT TV.

What resolution are you sending over what interface from your PC to your TV?

Which of the display modes as described on page 24 of your User Manual do you have selected?
 

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The fix is with the video card: Any not too old Nvidia-based or ATI-based, discrete video card -an actual card, not something built into the motherboard ("onboard")- should have the feature I'm about to describe. On-board video cards may not provide this HDTV-overscan-specific feature, some may:


My NVidia video card has some HDTV settings in it's control panel. (Advanced settings.) One setting is "resize my desktop to fit the screen" (or similar), which displays a 1920x1080 image with big green arrows in each of the four corners.


The arrow heads go far into overscan land.


There is a vertical slider and a horizontal slider that you drag to bring those green arrows in, out of the overscan area, until the arrow heads point perfectly at the four corners of the visible screen. (ok, you might have to use the Mits own pixel shift to get it perfect -but such a shift is secondary, not related to this video card feature)


Now, when those arrows are being drawn in the sliders, and the image seems to be getting smaller, the video card is NOT scaling the image -it's not down-sampling the original 1920x1080 output to fit into a smaller rectangle -no, it is actually chopping off pixels from the right, left, top and bottom of the 1920x1080 image. (a crop, instead of a resize)


From how far you had to drag the sliders to make the green arrows point to the four corners of the TV, the video card driver software determines the amount of overscan your TV has -in pixels- and chops your 1920x1080 resolution down that amount of pixels, like down to 1860x1036 as on mine.


The video driver then reports that lower resolution to Windows as the desktop resolution ("hey Windows, we don't have a 1920x1080p display after all, it's actually 1860x1036") -so all apps are resized to that, including the desktop, just as if you were connected to a lower resolution monitor.

Then, the key technology here:


While the driver reports the smaller 1860x1036 resolution to Windows, the video card actually outputs the full 1920x1080 to the TV -but as a 1860x1036 desktop rectangle drawn in the center of a full 1920x1080 black rectangle. In other words, as 1860x1036 rectangle with black borders on each side, making a full 1920x1080 image.


That full 1920x1080 image is rendered as usual by the TV, still 1-to-1 pixel ratio, but this time, the part of the image that goes into overscan land is those black borders, not your Taskbar and Start button.


It's a very cool solution indeed. All (cool) Windows applications support arbitrary desktop sizes, and many games do too now, because most games get their list of supported resolutions by polling Windows for it. So if Windows report 1860x1036 as a valid desktop resolution, that resolution will show up in the game's pick list.


I now see a resolution option of 1860x1036 in the Video Settings of my Lara Croft Anniversary game. And, my, does she look good on that 65" screen.



(Even at slightly less than 1080p resolution. That it chops/crops, not scales your resolution is also cool: it avoids a blurry output, preserves 1:1 rendering.)

I am still interested in mechanically moving the light engine/projector closer to the screen to defeat overscan. I don't like losing the edges of my movies. What works above for Windows and DirectX games cannot work for Blu-Ray movies. HD is 1080p, period. Scale it or chop it, it's no longer 1080p.



By the way:

A great way to check for how much overscan you have, and weigh it with a real world HD video, is to stream Netflix with an Xbox: the Xbox Netflix video player allows changing the video size between letterbox, stretch to screen, and others, but most interestingly, to "native" resolution, which shows a streamed 720p HD video (all they stream) as actually 720 pixels high (by 1280 wide?), centered on the screen. From that much smaller image, and flipping back and forth to the full size, you can see what you are losing at the edges due to overscan.
 

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Just remember when you set the resolution to less than the full 1920X1080 to see the desktop, you will not have 1:1 pixel mapping when playing a 1080i or 1080P video file. If you want the best picture quality when playing video files then you need to change the desk top resolution back to 1920X1080 when playing media files.


Mike T
 

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mtallent is right.


Hmmm, but I wonder if any NVidia or ATI driver knows to automatically switch to 1920x1080 when rendering video full screen. That would be cool. It's technically possible, since the card *knows* when it is playing an HD video. (the graphics cards have dedicated video rendering chips)
 

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Quote:
Originally Posted by thhowl /forum/post/17214120


mtallent is right.


Hmmm, but I wonder if any NVidia or ATI driver knows to automatically switch to 1920x1080 when rendering video full screen. That would be cool. It's technically possible, since the card *knows* when it is playing an HD video. (the graphics cards have dedicated video rendering chips)

I've not found any automatic way to do this, so I think the best solution is to have 2 monitors on the HTPC. I have a 22 inch LCD to display the desk top and then use my WD-65837 as the second monitor using "extended desktop" mode. I double click a media file and it launches Zoom player in a small window on the 22 inch LCD and automatically plays full screen (1:1 pixel) on the WD-65837, looks great and I can see all the controls and play time on the desk top monitor and use the computer for other things while the video is playing. ATI is now the ONLY video card that supports playing on 2 monitor at the same time and I also use XP for the same reason.


Mike T
 

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With the GeForce 6600 GT and the latest drivers (Vista 32 bit) I am having issues where when I resize the desktop with the 4 green arrows and hit apply, ok, the start bar and left side of the screen are still off screen.


Very wierd. It looks like it is going to work before I hit ok, I resize the screen and everything.


Oh well, anyone else have this issue?
 

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Quote:
Originally Posted by firstmode /forum/post/20678160


With the GeForce 6600 GT and the latest drivers (Vista 32 bit) I am having issues where when I resize the desktop with the 4 green arrows and hit apply, ok, the start bar and left side of the screen are still off screen.


Very wierd. It looks like it is going to work before I hit ok, I resize the screen and everything.


Oh well, anyone else have this issue?

This is not a very current GPU...


In any case the issues are as described above and assuming you can get the driver or your particular card to resize the desktop to eliminate overscan you will be pretty much ruining the image quality when you play content. You want to have some way to adjust desktop sizing when running stuff from the desktop and then an easy way to undo this scaling/sizing when playing content. I use a DUO.. That is not why I bought a DUO but it scales the Desktop nicely and when I play content I undo the scaling and let the overscan be whatever it will be to achieve 1 to 1 pixel matching.
 
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