composite video issues.

[bartre]

well, i received my new video card today.
installed it, working fine, but i tried to use the composite video output to plug it into the tv that i'm going to be using in my MAME cab, and i ran into a problem.
I turned the computer on, and the splash screen showed up, looked great.
the windows xp boot logo showed up, looked great.
the "welcome" screen showed up, and it was in black and white.
the picture was still a good quality, but there was no color.
the card is a Jaton nVidia FX 5200, as pictured.
i've tried a new cable, but beyond that, i don't really know where to go.

[Ummon]

Others have had a similar experience, I recall. You might find responding posts by monmotha or qrz.

[MonMotha]

In the nvidia control panel, you can probably configure the TV output for s-video or composite.  If you have things set up for s-video (likely the default), but only hook up the composite line, many configurations will give you B&W.

[DJ_Izumi]

It could be your composite video adaptor.  I've experianced some issues as well.

Some cards generate S-Video and you need an s-video to composite adaptor to get a composite signal.

OTHER cards have a 7pin adaptor and generate BOTH s-video and composite on the pins similtaniously, seperate pins being used for composite.  Special adaptors are sold with these cards that match the pinouts.

What could be happening is you're using the adaptor for one type on a card of othe other type and instead you're just taking the greyscale Luminance channel and feeding it out on a composite plug, thusly it has no color data.

Compare these:

ATI output pinout: http://pinouts.ru/Video/svideo_7pin_pinout.shtml
Standard S-Video output: http://pinouts.ru/Home/SVideo_pinout.shtml

Both of these use the EXACT same pins for S-Video, the ATI card uses it's extra pins for composite.  But look at this Nvidia layout

http://pinouts.ru/Video/nvidia_vidout_pinout.shtml

The same pins that an S-Video connector would use are NOT being used as par the s-video standard.  One is ground when the s-video standard would have it as color/chrominance.

You probably just have the wrong adaptor for the card.  I've personally experianced the issue you have and it was just an adaptor issue.  I suggest looking for one specificly for Nvidia cards

[MonMotha]

The card shown in that picture has an actual RCA jack on it for composite (presumably), so no adapter required.  I'm guessing this card just hooks that up to the luma signal on the TV encoder's output.  On most nvidia cards of that era, there was a setting in the driver for composite or s-video (Y/C).  nVidia cards of that era (especially the low end 5200) would not likely have the oddball jack on it.  That was usually used for cards that supported component (YPbPr) output.

The adapter that shipped with the card was often one of the passive combiners using a capacitor.  This will get you working composite on the s-video setting, but setting the output to actual composite mode would engage some filters that attempted to reduce cross luma/chroma artifacting.  The chroma output was then floated so that the capacitor meant to combine the chroma back with the luma wouldn't do anything.

Some cards did ship with an adapter that was just wires and no capacitor to combine.  With these adapters, you HAD to set things up in composite mode if you wanted color, since otherwise you were just hooking up to the luma line.  I suspect that's how the composite output on that video card is set up.  It would just be built on to the PCB rather than an external "dongle" style adapter.

Since the boot logos have color, this is clearly just a driver issue.  The color is disappearing right when the nvidia driver takes over.

[bartre]

okay, wow, that's a lot technical stuff.
but i understood it, which is a sign that i'm getting better at this stuff.
and yes, all signs point to this being a simple settings/driver issue, i was just checking if anyone had come across this before.