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8 bit VGA for PC XT

mbbrutman

Associate Cat Herder
Staff member
Joined
May 3, 2003
Messages
6,407
I have a PC XT in my office at work now, and I'd like to get a VGA card for it. If you have one you might want to part with, let me know.

If you have one and you don't want to part with it, please let me know the make and model so that I can make a list of what to look for.

Right now the machine has a monochrome card, 5151 monitor, 10MB hard disk and 512KB of RAM. When I get a VGA card it's going to be connected to a 21" flat panel LCD display. :)
 
Some 16 bit VGA cards will also work in an 8 bit slot.

The Original ATI VGA Wonder card is one that will. It will also drive
a 5151,5153, or 5154 monitor...as it has both 9 and 15 pin connectors.
This card came in 256KB and 512KB flavors.

There are also several 8 bit VGA cards , but I'm not sure of the
manufacturer. I have one , but it doesnt have a manufacturers
name. The BIOS chip, says AUTO VGA 2.17 copy. 1989 and it has
2 Cirrus Logic flat square chips, CL-GD510A and CL-GD520A
The card has FCC ID EKS56AAUTOVGA stamped on it. I think this may
be one of the generic cards that was sold by Jameco or JDR Microdevices
back in the 80's. Ebay is the place to look, thats where I got this one.
Good luck finding one.
 
Mike,

I have a no-name card here that looks just like a VGA Wonder, so it's probably a clone or re-badge (un-badge?) of the ATI. It's a 16-bit card, but I pulled it from an 8-bit slot in an XT. I used the motherboard in another machine, and it works fine, so I have no reason to believe the vid card doesn't work as well, although I haven't personally tested it. If you'd like to try it, just pay shipping (five buck$ will cover it). Pm your address.

--T
 
My ATI VGA Wonder can be seen in the link below, as it was in a PC/AT
I got from Erik awhile back.

http://www.vintage-computer.com/vcforum/showthread.php?t=3668

Erik posted a couple of photos of the machine, showing a side view
of the ATI VGA Wonder-16 board. I also have the original manual
from this card, which states that it can be used in a PC or PC/XT
8-bit slot. I think the dip switches on the motherboard need to be set
to no display or something like that. The machine unfortunately looks
a little different now :) , that original AT MB stopped working,
so I stuck an old 386/25 board in there. Still looking for a replacement
AT Model 339 MB.....
 
Ok, so I'm looking for early ATI VGA wonders as well.

I don't mind trying a few out, but I've blown my allowance trying to find 8 bit network cards. It's always good when I can get a pointer to known working combinations.
 
there's also a paradise card that works in either an 8-bit or a 16-bit slot. Some jamoke on I think the Tandy1000 yahoo group claimed that most 16 bit cards will work in an 8-bit slot. You might want to check out that thread. If that's where I saw it...
But yer a yutz regardless, being that you have a PGA card looking to be put to use. Fer shame!
 
That PGA card will get used, if it works. I'm afraid that was a salvage job, and it's got some twists in the boards. :-(

On the other hand, Computer Reset in TX sells PGA monitors still. Going OT here, if I don't have a PGA monitor what do I use?
 
either a multisync, older of course, or a VGA monitor. My Vermont Microsystems PGA clone plugs right into a NEC MII, or the IBM 5175. I had thought there was some weird syncing thing going on like sync on green, but apparently not. Unless the MII automatically looks for sync signals on the green input, but I really doubt it.
Hmmm but there are 2 "modes". One is digital color, the other is analog. Of course the MII can do both, but I'm thinking in (CGA) emulation mode, it probably puts out digital signals (TTL, 16 color). Where and how it makes the jump to analog color (it can do something like 256 simultaneous colors out of 4096) I ain't sure. If I find a VGA monitor around here cheap, I'll try connecting it. The O & A technical ref will probably have the right answers, but I seem to recall you have it too.
Regardless the connector is the same as a CGA/EGA, so the standard 9-pin cable will allow you to connect it to a multisync if you have one.
 
I don't have a tech ref on the PGA. Would like it - it would sure make programming the beast easier if I knew what to feed it. (My options and adapters set doesn't cover the PGA.)

If it's a 9 pin connector that is going to be a little bit of a trick to connect it to VGA. The MultiSync II has the inputs or a dongle to make it work, but most VGA monitors are 15 pin or BNC inputs.
 
"I don't have a tech ref on the PGA. Would like it - it would sure make programming the beast easier if I knew what to feed it. (My options and adapters set doesn't cover the PGA.)"

Hmmm, there must have been different editions. My set is 3 volumes. I planned to scan it in it's entirety (I think I brought it, but not absolutely positive). Found an HP scanner up here for $4...but then I found a job. I have to admit it's been getting in the way of some of my personal time. I'll have to take that up at the next union meeting...

"If it's a 9 pin connector that is going to be a little bit of a trick to connect it to VGA. The MultiSync II has the inputs or a dongle to make it work, but most VGA monitors are 15 pin or BNC inputs."

There are adapters that convert VGA to CGA. Or you can make yer own. Don't think Radio Shack sells that kind of stuph anymore, but you can buy hoods and whatnot from digi-key or active electronics etc. Or splice a vga cable into a cga. If I brought the manuals, I'll look it up in the next few days. I'm curious how that thing, which "boots" into CGA emulation mode, yet displays on the 5175 (which can only operate in one mode, analog, unless it's from another planet). My head is starting to hurt. Let me just peruse the manual.
 
I have a Paradise card in the box. On the box it says "Paradise Basic VGA Card, A video graphics card that features VGA, EGA, CGA, Hercules and MDA standards." On the end of the box it says "For IBM PC/XT/AT, PS/2 Models 25, 30 and compatibles."

The card is 8-bit with a standard 15-pin VGA connector and a DIP switch for selecting the mode. I had one many years ago installed in a Tandy 1000TX.

Kent
 
I was under the impression that PGA used a 2 or 3 card set. (I may be mixing that up with the 3270 tho). Years ago I had a IBM PGA monitor which I was never able to find a card(s) for. I must have abandoned it in one of my moves. Mueller has a bit of specs on it. I have a book called "Programmers Guide to PC and PS/2 Video Systems" by Richard Wilton. MS Press. There's a blurb on the cover that the C Gazette named it the "1989 Book of the Year". No mention of the PGA however. Has all the other video modes tho. If it might help I could send it to you.

Lawrence
 
I sure was SAD when Hercules went under. I used 2 of the video boards with great success for years. Then one day I guess they got purchased by another company then poof gone.

Edit - ooooooo, I guess Not Gone. Looks like they just don't do video cards anymore. I don't blame them, I wouldn't want to go up against ATI and all the rest of the modern video card makers.
 
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The PGA is a 3 card set. Sandwiched very tightly together, and it takes two slots in the machine. It's a fairly intelligent beast too - it has it's own 8088 class processor on board to do the drawing.

Btw, that link is awesome! There is very good overview information there about the PGA.
 
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there's also a reprint of an IBM Technical Journal article about the PGA. I can't remember where I found it, but I'm sure it would turn up as easily for anyone else. Mostly a rehash of the stuph to be found in the O & A Tref.
 
PGA is 9pin and uses combined sync AKA RGB+S and runs at 640x480 res just like VGA the BEST clone monitor for PGA tends to be the NEC Multisync ORIGINAL, the II should work but not sure if the pinout is identicle, there used to be adapter cables available specific to those old screens. If you can get the pinout and break out PGA to BNC connectors then you have a wide range of choices on the screen

Good luck
 
the Multisync II works as well. AAMOF the II offered more compatibility with a wider range of stuph, including monochrone, then the original. The pinout of the PGA is identical (in a sense) to the CGA/EGA, in that you can use a standard 9 pin CGA/EGA cable and plug it into a MII just as if it were a CGA/EGA. There is something going on with the sync signals. I'm taking what you said to mean there's a seperate distinct input for the combined sync signals. Ok, then that would mean the MII has the ability to tap both off of the same input. I went to bed early last night and slept 13 hours, so I didn't go looking for the manual. I should get to that tonight, and file a report early in the week. Yawn.
 
I have actually used the original with monochrome and it seems to work great, I've never gotten the Analog on mine to work however, I must not have the right pinout or something is broken. (I am trying to use it with proprietary stuff though)

It seemed to fire up with EGA CGA and hercules, it also worked OK with an oddball Cornerstone adapter and a strange methus 9pin fix freq video card I have.
 
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