How do I best deal with overscan on my philips LCD tv when connecting it to a computer?

March 3, 2007 2:25 PM

How do I best deal with overscan on my philips LCD tv when connecting it to a computer?

I've long had a media PC hooked up to my TV. Until recently I had non-HD CRT and I had it hooked up to my computer via a VGA-to-svideo converter. It had overscan adjustments so I could set the level of overscan and the position of the image on screen.

I hook up my computer to my philips LCD TV via the HDMI connection (using a DVI to HDMI cable). I set the right modeline for the TV and I get a nice high-res picture.

But, it's overscanned by about 3-4%, that is, about 20 pixels on all sides. When watching content, no problem. When using the TV as a computer display, it sucks. Menu bars on full screen programs are not visible. The status bar at the bottom is not visible. In text-modes the bottom line and several characters on each line are not visible.

The media computer runs linux, and typically I run it with no display manager (the software I wrote to run my media stuff acts as a primitive display manager). I launch most programs in full screen. I am willing to use a window manager as long as it's small and fairly fast (media PC is very modest). I need no other features than the ability to say "the usable window of the display is from X1,Y1 to X2,Y2, treat everything outside of that as not part of the display"

Alternatively, if anyone has had any luck altering their modelines to reduce the overscan, or altering their screen resolutions to the actual shown pixelage, that would be great. All attempts I've made at altering the mode line have made no difference, until they diverge from the standard mode line too much, at which point they don't work at all.

posted by RustyBrooks to computers & internet (3 comments total)

With my Sony HD CRT, I discovered that there is a "maintenance menu" that you can access through a special combination of button presses on the remote. It lets you adjust the size of the image on the screen just like you can with a monitor. I did this when I set up MythTV, and it worked out well. I suggest you Google for the model number of your TV and "maintenance menu" and see what you can find. In my case, the settings that are available all have incomprehensible names, so I needed a maintenance guide to help me figure out which ones controlled the stuff I wanted.
posted by autojack at 3:19 PM on March 3, 2007

xvidtune is your friend when it comes to adjusting modelines to remove overscan.

I'm having the same problem with my LG, although it does support a few pixel mapped modes, it doesn't support 1366x768. :(

I was able to get the overscan down to about 2%, which is perfectly usable, although not nearly as nice as a one-to-one mapping.
posted by wierdo at 3:44 PM on March 3, 2007

Maintenance mode doesn't have the ability to adjust overscan - I checked. (avforums and what not)

xvidtune doesn't work for me on my LCD tv. Whenver I use it, no matter what (i.e. even if I don't adjust the settings) it won't let me apply them. I know how to adjust modelines, and I've done so manually... they either seem to have no effect, or it won't allow me to use them (screen goes black). I suspect that my TV just plain won't accept modelines that are too far from it's built in modes, and that it automatically adjusts modlines that are close to match an internal modeline - in fact, when I look at the current mode in xvidtune, it always shows me the same thing (the built in modeline for 1280x720)

Overscan of 2% would still be 7 pixels on top and 7 on bottom. 12-ish on left and right each. Better than 3 or 4% but still...

Anyway, I've very nearly given up on getting it to not overscan and at this point I just want to find some way to make X just ignore the parts of the image that are offscreen. I saw a hack for KDE somewhere, I think, where they just created 4 custom menu bars and sized them to match the offscreen space. KDE won't put windows over the menu bars so effectively this reduces the usable space, which is more or less what I want. I don't want to run KDE though, for an application that essentially doesn't need ANYTHING from a window manager. A solution for fvwm or something else suitably small/fast would be great.
posted by RustyBrooks at 7:47 PM on March 3, 2007