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386 or 486 with Hercules/MDA as primary or only graphics adapter

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AlexC

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For various mildly pointless reasons, I'd like to run a 386 or 486 with a Hercules/MDA graphics adapter as the primary or only display. It's simple enough to have EGA or VGA as the primary display and Hercules/MDA as the secondary, but so far I've had no luck getting anything other than my XT clone to boot directly to a Herc/MDA screen as the only display.

Closest I've come is with a Paradise Autoswitch EGA480 card which will boot while connected to a monochrome monitor, including allowing me to access the BIOS. That's fine, but the card doesn't do full Hercules (sync is out of range on two monitors I tried), only text modes and some not-very-useful EGA graphics modes.

I have a 386 board with a 'mono/color' jumper, but regardless of that setting and/or setting the BIOS display type to 'Monochrome' I always get a CMOS display mismatch error (as reported to the VGA screen) if trying to boot with two cards, and no display at all if booting to just the Hercules/MDA card.

I know I could just put 'mode mono' in the autoexec.bat file but that would leave me unable to enter the BIOS or see any config.sys messages at boot time.

So I'm curious: has anyone set up a 386 properly with Hercules/MDA only, including BIOS access?
 
Yes. I had an old 386/25 system that had a genuine IBM MDA adapter and IBM 5151 monitor on it, running Linux as a Radius server in the late 90s. The BIOS setup (AMI BIOS if I recall correctly) was accessible. I did have to set the graphics card type in BIOS to use the monochrome first, then removed the VGA card from the system.
 
Thanks. That's what I'd have expected but it's not what I'm seeing. I wonder if proper support was dropped sometime in the mid-386 era? This board is from May 1994 and the BIOS offers 'Monochrome' as an option, but I've seen online that some others offer 'Hercules' so perhaps that's the problem.
 
By the time of the 80386, Hercules monochrome adapters far outnumbered the somewhat clunky IBM MDA.

But yes, I've used the Hercules adapters routinely on the 80386 and 8046 machines. I don't recall if I tried them on Pentium 1 systems, though--PCI VGA cards were cheap and plentiful.
 
I can use the Hercules card as a secondary display device in all the 386 and 486 machines I own, but bizarrely the only one that will allow it to be the primary or sole display adapter is a Toshiba T3200SX portable. Using test3.exe to disable the internal VGA adapter entirely allows me to boot directly with the Hercules card and monochrome display.

The only quirk there is that the default Hercules font in 90-column graphics-text mode is serif, whereas on all other machines it's san-serif. No big deal but I've no idea where it's getting the font from - I guess the machine's own BIOS?
 
IDK it should be trivial to run Herc/MDA only. Just set in the BIOS. Most 386/486 should support it. All my socket 7 boards support mono primary and I've used it a couple times. I don't think mono primary support was dropped until AGP.

Have you tried a different video card? Maybe there is some incompatibility with that particular board.
 
Yes, I used to run HGC clones in 386/486, as the only display, without any problems.
It was pretty common to use HGC in servers - they never entered graphical mode anyway, so why use a better card?
I even tried HGC in Athlon ISA/PCI/AGP mobo, with mixed results: one card did work, the other didn't.
I expect problems with boards equipped with AMI Winbios (BIOS with GUI, the utter abomination!), though, as that GUI seems to use EGA graphics mode.

BTW, a challenge for people with 386+ and HGC at hand: try running Windows version as new as possible:
Windows 3.1 comes with Hercules Monochrome driver, so nothing interesting here.
Windows 3.11 lacks such a driver, but it can be downloaded and added during install, still nothing special.
Windows 95 officially requires VGA, but you can install it by upgrading 3.1x, and it will use 3.1x Hercules driver.
In theory, it should work with Windows 98 and ME as well, but I've never tried it nor saw any success reports - anybody willing to try?
 
Ah, good points. I hadn't considered that the card might not be quite up to scratch. I've tried two but they're basically identical, based on a Winbond chip. Both cards work fine in an XT-class machine, in the Tosh T3200SX and as a second display in my 386/486 PCs (though not perfectly in one 486 with VL graphics: GW-BASIC and Windows 2.03 both hang). I have a different card on the way so I'll report back after testing that.

I hadn't considered Windows 95 but Win 3.11 was one reason for wanting this on a 386, along with WordPerfect 5.1+, whose ScreenExtender utility can handle Hercules modes.
 
Odd. It just started working in a 386DX/40. I left the mono/color jumper open, set the BIOS type to 'Not installed' while using a basic VGA card alongside the mono card, switched off, removed the VGA card and now the Herc setup works fine, including allowing me to get into the BIOS. I'm fairly sure I tried those settings before, so I don't know why it's working now.

First quirk: this 386 has yet another different font for Hercules graphics-text modes (e.g. Ability Office, slhed.com, Windows 2.03 startup screen, etc.). I had no idea Hercules display fonts depended on the host PC's BIOS.

Second quirk: GWBASIC reliably hangs if loaded in 'mode mono' in a two-card system. It doesn't hang on the same system if run in 'mode co80'. I guess it must do some display checks and get confused.
 
And now I've got it working in a 486 board with VL-Bus graphics built into the motherboard. There's a jumper to 'disable VGA' on the motherboard but that's not enough: I had to remove the VGA BIOS chip entirely.

Now it behaves like a Hercules-only machine. And, once again, it has a different font (quite a nice one).
 
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