AW: CGA card (Mitsubishi Electric) with 192K RAM?

Doug Jackson doug at
Tue Sep 8 18:16:42 CDT 2020

I recall some of the high end cards in the CGA / EGA era had adon boards
that were connected with a 20 or 36 pin jumper cable across the top of the
boards - They also ran more than 64K or ram, such as the ATI Wonder
boards.  Maybe it's like that - the ATI boards had 256K so they could page.

Kindest regards,

Doug Jackson

em: doug at
ph: 0414 986878

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On Wed, Sep 9, 2020 at 9:04 AM Fred Cisin via cctalk <cctalk at>

> On Tue, 8 Sep 2020, Jules Richardson via cctalk wrote:
> > OK, it boots off a DOS 3.3 floppy if that floppy is inserted before it
> > attempts to boot from the hard disk. If I wait for it to do its "system
> file
> > not found" bit, followed by a subsequent prompt to insert boot media and
> > press a key, it attempts to access the floppy drive but then goes off
> into
> > la-la land. Odd.
> How large is the drive?
> If it is over 32MB, then try to find DOS 3.31 or newer.
> MY preference is MS-DOS 6.22
> > But anyway, taking the successful floppy boot route, I can certainly
> access
> > the hard disk in terms of bringing up directory listings and TYPEing
> files to
> > the display. So far, attempts to run anything from the drive just result
> in a
> > lock-up (keyboard immediately unresponsive, hard reset required). There
> > appear to be DOS utils on the drive, and, but I've not
> checked
> > for hidden system files yet. fdisk shows the partition as active.
> Date and time of and any other DOS files will identify the
> version number.
> DIR /A  or
> DIR /A:H
> will let you see the hidden files (presumably IO.SYS and MSDOS.SYS; PC-DOS
> had IBMBIO.COM and IBMDOS.COM instead)
> Can you COPY files from the HDD to floppy?
> Being able to access contents of files, but not RUN them seems odd.
> IF the DOS on the floppy misunderstands the partition table, then root
> directory might look OK, but sub-directories might not be where it thinks
> they are, . . .
> >> Got an IBM "Advanced Diagnostics" floppy to try?
> > No, but I see that the minuszerodegrees site has an image, so I'll write
> that
> > out and see what happens.
> NOT a big deal.  It's merely the only method directly from IBM for doing
> low level format.
> In most cases, Speedstor is more useful for LLF.
> > Looking at the drive contents, incidentally, I didn't see anything that
> > explains (or interacts with) that unusual video hardware - it basically
> just
> > holds DOS and a bunch of documents written by the original owner. Maybe
> they
> > got suckered into buying this fancy graphics hardware without having any
> > actual need for it, and then of course EGA and VGA came along and
> rendered it
> > obsolete anyway.
> It is probably completely CGA compatible, unless you invoke of of its
> other modes.
> The ROM on the video card may be a BIOS extension, in which case access to
> extended modes may be handled internally in various programs.  For
> instance Windows 3.x, PC PAint, Pagemaker, and Xerox Ventura let you
> configure for a variety of video hardware.
> Otherwise, check to see if CONFIG.SYS has DEVICE commands to load any
> device drivers, usually .SYS, although sometimes .COM
> >> XT controllers tended to NOT be interchangeable, even between various
> OEMs
> >> of Xebec!
> > Yes - something that people often seem to forget, too. I've run into
> that
> > quite often, where someone will hang onto an old drive because of the
> > contents, but they'll dump the controller that it was formatted against.
> It always seemed counter-intuitive that makers of HDD hardware for XT
> didn't slavishly mimic IBM's XT HDD.  And especially counter-intuitive
> that different vendor Xebec controllers didn't always interchange.
> --
> Grumpy Ol' Fred                 cisin at

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