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Introduction

I know someone who has a laptop and wants it to output video to a TV. I bought a cheap cable to connect its VGA output to one of the TV's composite video inputs.

The seller of the cable clearly said that the laptop must support TV-out via the VGA socket, but I assumed this would be true. This assumption may not be correct.

Specs

  1. GPU: NVIDIA® GeForce® 9300M GS
  2. Video outputs: VGA, HDMI
  3. Cable: VGA to Composite & S-Video (not active, no scan converter)
  4. TV: Standard definition (SD). Non-widescreen. Supports PAL, NTSC and SECAM.

Problem

The problem I have run into is Windows will not allow me to set a compatible resolution to use for the TV. Consequently, the TV just shows the typical sort of distorted images you get from a mode mismatch. I figure there's no EDID information provided to Windows, so it's just using a generic non-PnP monitor driver.

I looked through Windows' list of built-in monitor drivers, and the closest driver I could find was Generic Television. However, even using this driver, Windows seemed to provide the typical list of VGA monitor resolutions. The minimum resolution I could set was 800x600, and the minimum refresh rate was 60Hz.

I think there could be multiple problems here that I need help with:

  1. The Generic Television driver doesn't seem to provide the right modes, namely 480i @ 60Hz and 576i @ 50Hz. I think I need a suitable monitor driver.
  2. Windows seems to have a minimum resolution of 800x600, which is too high.
  3. Windows seems to have a minimum refresh rate of 60Hz.

It's possible that the last two problems will be resolved in the presence of a suitable monitor driver.

Lastly, I would prefer an option other than using PowerStrip, since it's commercial software.

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I've had no problems running a CRT TV at 1024x768 via composite. The desktop was a bit squished in, but it was all there. –  Ignacio Vazquez-Abrams May 19 '13 at 4:02
    
@IgnacioVazquez-Abrams, this is a standard-definition TV, and it just shows a severely distorted image (or just flickering) when it isn't set to an appropriate mode. I couldn't think of the right terminology to explain this when I wrote the question! I've updated it to reflect this. –  Sam May 19 '13 at 7:09
1  
They can't handle higher resolutions; the video card compresses the image in order to fit the television. –  Ignacio Vazquez-Abrams May 19 '13 at 8:07
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"I obtained a VGA to composite/RCA adaptor" -- Please be more specific. You need a (active) converter, not a (passive) adapter. Some older graphics cards had a built-in "TV output" that converted the VGA to NTSC (aka analog SDTV), which is probably what @IgnacioVazquez-Abrams is referring to. I've used that to display a (converted) 1024x768 desktop on a TV, but regular text is very hard to discern and read. It is not a question of resolution. You need a scan converter. Without a converter there is no driver or adapter that can convert VGA to a composite TV signal –  sawdust May 19 '13 at 22:08
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@sawdust: Some video cards output a TV signal on one or more of the DE-15 pins; a passive converter is suitable for those. It does require video card support though. –  Ignacio Vazquez-Abrams May 19 '13 at 22:23

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