Interesting...seems the Olivetti card I got recently also can do this mode:
Olivetti GO423 (Positive Graphics Controller)
https://minuszerodegrees.net/manuals/Olivetti … 20computers.pdf
Havent tested it so far and dont think it works without repair.

ZSoft PC Paintbrush from 1985 lists some more 640x400 monochrome modes:

AT&T 6300 High Res
Corona Computer
Persyst BOB Board
Tecmar Graphics Master (but there's also the 16-color mode)

Jo22 wrote on 2023-03-24, 13:14:

Sadly, I couldn't find any information about the last video type (VAXM). Any ideas ?

Must be DEC VAXmate - https://www.vt100.net/manx/details/1,3548

Grzyb wrote on 2023-03-25, 11:10:

Jo22 wrote on 2023-03-24, 13:14:

Sadly, I couldn't find any information about the last video type (VAXM). Any ideas ?

Must be DEC VAXmate - https://www.vt100.net/manx/details/1,3548

That's it! Thank you very much, Grzyb! 😃

Predator99 wrote on 2023-03-24, 21:15:

Interesting...seems the Olivetti card I got recently also can do this mode: Olivetti GO423 (Positive Graphics Controller) https: […]
Show full quote

Interesting...seems the Olivetti card I got recently also can do this mode:
Olivetti GO423 (Positive Graphics Controller)
https://minuszerodegrees.net/manuals/Olivetti … 20computers.pdf
Havent tested it so far and dont think it works without repair.

Interesting! I hope it can be fixed, eventually. 🙂👍

Grzyb wrote on 2023-03-24, 21:47:

ZSoft PC Paintbrush from 1985 lists some more 640x400 monochrome modes: […]
Show full quote

ZSoft PC Paintbrush from 1985 lists some more 640x400 monochrome modes:

AT&T 6300 High Res
Corona Computer
Persyst BOB Board
Tecmar Graphics Master (but there's also the 16-color mode)

I know the first one, but the rest is new to me. I'll have to check these out. 🙂

There were two approaches to the 640x400 resolution:
- use a regular CGA monitor (15 kHz HSYNC) with interlace, eg. Tecmar Graphics Master
- use a dedicated monitor (most likely 31 kHz HSYNC), eg. DEC VAXmate

The Olivetti, Compaq, and Toshiba should be the same mode as the AT&T 6300's. AT&T's machine was a rebadged Olivetti M24; the Compaq Portable III (and 386) implemented a compatible video subsystem, as did Toshiba's T3000/T5000 series.

IIRC, some pre-EGA GRiD machines (GRiDCase 15x0?) were compatible with it as well. 640x400 was popular with early portables, since they could easily pixel-double CGA graphics and still offer crisper 8x16-dot text.

The Tandy 2000 (not quite PC compatible) also had a 640x400 B&W video mode. Probably more widely used than its color counterpart - 31 KHz color monitors were expensive, and the 2K's hi-res color mode was extremely S-L-O-W due to the architecture.

Thanks for the replies, guys! 😃👍

I've just found another interesting PC with a 640x400 CGA: It's the NCR PC4 or PC4/i (more IBM compatible).
It comes into two versions, colour (640x400 CGA) and mono (720x348 Hercules emulation).

What's funny, though: It's an 1985 Apple Lisa look-a-like running GEM that had won a German Design Award. 😄

https://www.old-computers.com/museum/computer.asp?st=1&c=539

https://www.youtube.com/watch?v=JmvPSmirrow

Edit: Here's a video about the colour/CGA version. The font isn't that bad, imho. 🙂👍

https://www.youtube.com/watch?v=Ugw5ij9rcAk

Edit: Here's a close up shot of the text font:

https://www.youtube.com/watch?v=cmm4cAgsHZo&t=400

Edit: If I do understand correctly, there's even a 640x400 4 colour, progressive scan mode in addition to a 640x400 mono mode.
If that's true, let's imagine this was more mainstream..
CGA games could have looked so much better, much more detailed (4 times the pixels).

Mi toshiba cga have 640x400

Wasn't there some kind of PC emulator or compatibility card for the Atari ST that supported 640x400 monochrome mode as well? It may have been 100% compatible with the M24 / AT&T 3600, but I'm not sure.

digger wrote on 2023-05-27, 18:22:

Wasn't there some kind of PC emulator or compatibility card for the Atari ST that supported 640x400 monochrome mode as well? It may have been 100% compatible with the M24 / AT&T 3600, but I'm not sure.

Yes, PC-Speed by SACK Electronic (a board that needs soldering), this review mentions the Olivetti graphics mode. It will need the ST monochrome monitor, of course.

My uncle in the US had a PC/AT compatible 286 system from Wyse, with a monochrome monitor.

The graphics adapter in that system was CGA compatible, but I remember my uncle being particularly proud of its enhanced super high resolution capabilities. I believe it was a major factor when he chose to buy that model.

I remember being in disbelief of the resolution he claimed that the system supported, and I recall him showing me a demo that I assume came with the system, which showed those enhanced capabilities. I believe one of the images showed the head of a tiger, drawn in a paint program.

So I just did some searching on-line, and this system was probably a WysePC 286 (WYSE-2100 Series) machine, and the graphics adapter was likely a Wyse WY-700.

First of all, this card supports a 640x400 mode, which means it qualifies to be added to @Jo22's list. It even offers 4 shades of grey in that mode.

But get this: its maximum resolution was 1280×800, which was crazy high for a system that came out in the mid '80s! In that mode, only back and white is supported, so no multiple shades of grey. But still!

More info in the Wyse WY-700 video adapter: https://www.seasip.info/VintagePC/wy700.html

I wonder if he still has that old computer stored somewhere. I'll ask him some time.

digger wrote on 2023-06-01, 14:28:

So I just did some searching on-line, and this system was probably a WysePC 286 (WYSE-2100 Series) machine, and the graphics adapter was likely a Wyse WY-700.

First of all, this card supports a 640x400 mode, which means it qualifies to be added to @Jo22's list. It even offers 4 shades of grey in that mode.

But get this: its maximum resolution was 1280×800, which was crazy high for a system that came out in the mid '80s! In that mode, only back and white is supported, so no multiple shades of grey. But still!

That was good for its time for sure, but some of that card's contemporaries did even more:

- Matrox's PG-1280A offered 1280×1024 in 256 colors
- Sigma Designs' LaserView did 1664×1200 in 4 shades of grey
- and in pure 1-bit monochrome, something called the Conovision 2800 from Conographic went as high as 2880×1024

Here's a little comparison chart from PC Magazine, which is part of a detailed review of the boards mentioned: https://archive.org/details/PC-Mag-1987-05-26 … up?view=theater

...But hey, this is all 1986/7 tech. Way back in 1982, Control Systems (which later became Artist Graphics) had the ARTIST 1, with 1024×1024 in 16 colors (or shades of grey): https://archive.org/details/PC-Mag-1982-12/pa … up?view=theater

VileR wrote on 2023-06-15, 19:55:

- Matrox's PG-1280A offered 1280×1024 in 256 colors

Wait... Wasn't this before the VGA era, that replaced TTL with analog signalling, allowing for a theoretically infinite number of colors to be shown on the screen at the same time?

Does that mean that Matrox introduced a proprietary signaling standard as part of this graphics card? That would also have required a proprietary monitor, right?

Anyway, in my opinion, the era alone should not determine whether a proprietary video standard should be considered "CGA on steroids". At a certain point, it's just a competing graphics standard. Even if CGA compatibility is the highest standard fall-back mode that it is compatible with. Otherwise, even IBM MCGA would make this list.

digger wrote on 2023-06-16, 17:10:

Wait... Wasn't this before the VGA era, that replaced TTL with analog signalling, allowing for a theoretically infinite number o […]
Show full quote

VileR wrote on 2023-06-15, 19:55:

- Matrox's PG-1280A offered 1280×1024 in 256 colors

Wait... Wasn't this before the VGA era, that replaced TTL with analog signalling, allowing for a theoretically infinite number of colors to be shown on the screen at the same time?

Does that mean that Matrox introduced a proprietary signaling standard as part of this graphics card? That would also have required a proprietary monitor, right?

Anyway, in my opinion, the era alone should not determine whether a proprietary video standard should be considered "CGA on steroids". At a certain point, it's just a competing graphics standard. Even if CGA compatibility is the highest standard fall-back mode that it is compatible with. Otherwise, even IBM MCGA would make this list.

I have always thought the CGA+ / EGA+ high res options beyond the standard modes used analog monitors, probably multisync. Likely used the same 9pin D connector at first. These were available throughout the 80s, probably more in high end professional work. They were called CGA and EGA compatible because they had to work on an IBM PC which they were installed in, and most software had to have. Then they'd launch the software and they could access high res graphics mode, but as people will mention, they usually supported larger text modes too, which was supported by several packages on the market. The first higher res + more "color" I remember I think was with a PS/2 VGA monochrome monitor, which would have been a late 80s thing, running something like the original IBM VGA. Obviously the monitor was analog, which likely was similar to those other early ones, so that is why I mention it. I wish I still had that monitor, as I'd like to review what else it could have been compatible with. As you know, analog support has changed over the years, so the earlier, the more interesting when it comes to these early products.

digger wrote on 2023-06-16, 17:10:

VileR wrote on 2023-06-15, 19:55:

- Matrox's PG-1280A offered 1280×1024 in 256 colors

Wait... Wasn't this before the VGA era, that replaced TTL with analog signalling, allowing for a theoretically infinite number of colors to be shown on the screen at the same time?

Does that mean that Matrox introduced a proprietary signaling standard as part of this graphics card? That would also have required a proprietary monitor, right?

The PG-1280A by Matrox is meant as enhanced PGA ("Professional Graphics Adapter") clone. The PGA introduced analog RGB at 640x480 a long time before VGA. The video timings used by the PGA are not entirely the same as VGA (30.5kHz instead of 31.5kHz), also the PGA uses composite sync instead of separate sync. Nevertheless, Analog RGB was already there. Heck, even the (non-PC) Amstrad CPC series used analog RGB (at PAL/NTSC timings), but was limited to three shades of R, G and B, offering 27 colors in total. IIRC, the 80-column mode on the C128 also used analog RGB.

The high-resolution timing of the PG-1280A is definitely proprietary, as any high-resolution mode in that era was proprietary.

mkarcher wrote on 2023-06-16, 19:53:

digger wrote on 2023-06-16, 17:10:

VileR wrote on 2023-06-15, 19:55:

- Matrox's PG-1280A offered 1280×1024 in 256 colors

Wait... Wasn't this before the VGA era, that replaced TTL with analog signalling, allowing for a theoretically infinite number of colors to be shown on the screen at the same time?

Does that mean that Matrox introduced a proprietary signaling standard as part of this graphics card? That would also have required a proprietary monitor, right?

The PG-1280A by Matrox is meant as enhanced PGA ("Professional Graphics Adapter") clone. The PGA introduced analog RGB at 640x480 a long time before VGA. The video timings used by the PGA are not entirely the same as VGA (30.5kHz instead of 31.5kHz), also the PGA uses composite sync instead of separate sync. Nevertheless, Analog RGB was already there. Heck, even the (non-PC) Amstrad CPC series used analog RGB (at PAL/NTSC timings), but was limited to three shades of R, G and B, offering 27 colors in total. IIRC, the 80-column mode on the C128 also used analog RGB.

The high-resolution timing of the PG-1280A is definitely proprietary, as any high-resolution mode in that era was proprietary.

Interesting. I've found the matching advertisement in a twitter post.
Since some of us don't, err, like the platform, I've attached it here. It's just an ad, so that should be okay.

Fascinating. Thanks for clarifying and digging up additional info! (Shouldn't I be doing the "digging"? Ha! 😉)

However, I really think such cards deserve a topic of their own. These standards are way beyond "CGA Plus" territory. I think the spirit of @Jo22's topic here is cards that extend the CGA standard with higher resolutions and/or multi-color graphics modes other than those of Tandy/PCjr, Hercules and EGA, while still using TTL RGB signalling to drive the monotor.

That should summarize and scope it well, do you think? 🙂

I’m uncertain what type of video card it was but the original NCR 286 machines had a custom 640x400 monitor and video card at the time I could never figure out what it was compatible with so was stuck with plain CGA in graphics mode.

Color text was beautiful