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derdup
July 24th, 2008, 06:32 PM
Hi friends,

I have a functioning 386 which displays VGA color with no problems on an old (small) monitor. When I hook it up to a newer SVGA screen, it is defaulting to VGA monochrome.

I've tried using the MODE command in MS-DOS but this has no effect.

My guess is I need to re-configure the dip-switches on the graphics card. There are 4 switches, all OFF except switch 1.

The card is an ORCHID 0-VGA-30449 and dates from 1988. Does anyone out there have the info on these switches?

I've noticed that the pin arrangement of the 2 monitor cables differ. Is this an issue here also?

Thanks,
Harry

Terry Yager
July 24th, 2008, 08:29 PM
How much RAM? I'm guessing 256 or mebbe 512K, which probably won't display higher rez than 640 x 480. 1988 is pretty early for a generic VGA card. No telling what kinda weirdness it might be doing. Of course, with only four switches, it shouldn't take long to try all 16 combinations and see what happens...it shouldn't fry anything (I hope...YMMV).

--T

derdup
July 24th, 2008, 09:18 PM
Hello Terry,

I think my card is 512k and, as you say, won't handle high resolutions. But I was expecting the monitor to provide the bare minimum VGA with (16?) colors.

I am running Windows 3.1 and there's a funny thing here,....when windows starts to load, the splash screen appears IN COLOR!.....but then everything goes back to gray.

16 dip-switch combinations isn't too bad but I'll wait a little while first. Some kind soul might have the official settings and save me the trouble.

Cheers,
Harry

Chuck(G)
July 24th, 2008, 10:17 PM
Here's a thought.

Older monitors used pins 4, 11 and 12 on the video connector to signal what kind of monitor was attached. In particular, pin 12 is the one that signals a monochrome VGA monitor.

Unfortunately, pin 12 is used for a different purpose in newer DDC "plug and play" monitors.

I don't know if your Orchid card looks at the monitor ID pins, but it's reasonable to suspect that it does.

Basically, here's the functioning of the monitor ID pins:


4 11 12
ID2 ID0 ID1

n/c n/c n/c no monitor
n/c n/c GND Mono monitor which does not support 1024x768
n/c GND n/c Color monitor which does not support 1024x768
GND GND n/c Color monitor which supports 1024x768

As I said, this is just a guess, but temporarily making pin 12 NC might clear your problem up.

paul
July 25th, 2008, 02:16 AM
Perhaps it's a Prodesigner -II with ET4000 chip, look here:

http://stason.org/TULARC/pc/graphics-cards/M-O/ORCHID-TECHNOLOGY-XVGA-PRODESIGNER-IIS.html

But I think the previous poster is correct in this case.

mikey99
July 25th, 2008, 12:51 PM
Awhile back I got an ATI VGA Wonder card and hooked it up to a VGA
monitor and it only displayed in monochrome. I thought the card was bad
but later found that it has a setup program in the VGA card BIOS which
is accessible by running a program on the diskette that came with the card.
I went into the BIOS setup and there was a setting for monochrome which
I changed to color, then it displayed in color :-)

derdup
July 26th, 2008, 04:16 PM
Thanks for all the replys.

Unfortunately I have no diskette for this old card so I can't explore the possibility of there being a BIOS setup option.

As Chuck suggests, the pin arrangement of the video plug would seem to be the likeliest cause of this situation. When I get the time I'll do some modifications and let you know how it goes.

Thanks everyone.

paul
July 27th, 2008, 12:57 AM
I am pretty much 100% sure this card has no built-in setup like the ATI. I had an ATI Mach (something) way back when, and numerous Orchids, and the later is configured with a utility on every boot, vmode.com, if I recall.