BitWrangler wrote on 2024-09-24, 03:27:

Why am I thinking there was something about needing a V20 because of 186/286 instructions.... or was that windows drivers?

Or maybe the VGA BIOS needs 386+, even. The chip is dated '94.. 🙁
By that time, about everyone was into fast 486 PCs and WfW 3.11.

Last stand for 286 PCs and pure 16-Bit hardware/software was 1992, I often think.
By 1993 onwards, DOS extenders such as DOS4GW and memory managers like QEMM were all the rage.

Trident 9000 is like a low-end version of Trident 8900, I think. Could be wrong, though.
I had trouble with those Trident 9000 in my 286es, as well.

Cards that should work with XT/AT PCs include the old Paradise PVGA1A, I think.
It sometimes pops up on German eBay here. Old OAK cards also worked in my 286.

PS: You're right. That was the Windows 3.0 driver for VGA 640x480 16c.
There's an 8088 patch at vcfed forums. 😀 MCGA/VGA Mono driver did work on XTs without any patch, I think.

Kinetix - nice! I thought about doing something like this after I did it the way I did, but since I only have a single machine I figured I'd leave it. My 5150 has been put up for a bit while I work on other systems - next time I get it out I'll have to see if I have this same intermittent problem.
If we manage to get a list of cards that work it would be great!

TheRealAnubis wrote on 2024-09-24, 12:53:

Kinetix - nice! I thought about doing something like this after I did it the way I did, but since I only have a single machine I figured I'd leave it. My 5150 has been put up for a bit while I work on other systems - next time I get it out I'll have to see if I have this same intermittent problem.
If we manage to get a list of cards that work it would be great!

I've seen at least two listings for working cards, on PC and XT.

Search for "8bit Friendly ISA VGA cards" on the VFC forum:
https://forum.vcfed.org/index.php?threads/8bi … ga-cards.26866/

The other listing is "IBM 5150 - VGA Cards" on minuszerodegrees:
https://www.minuszerodegrees.net/5150/vga/5150_vga.htm

now I´m thinking about the resistor, as recommended. I´ll see how to do it, before any testing, just in case

kinetix wrote on 2024-09-24, 23:19:

I've seen at least two listings for working cards, on PC and XP. […]
Show full quote

TheRealAnubis wrote on 2024-09-24, 12:53:

Kinetix - nice! I thought about doing something like this after I did it the way I did, but since I only have a single machine I figured I'd leave it. My 5150 has been put up for a bit while I work on other systems - next time I get it out I'll have to see if I have this same intermittent problem.
If we manage to get a list of cards that work it would be great!

I've seen at least two listings for working cards, on PC and XP.

Search for "8bit Friendly ISA VGA cards" on the VFC forum:
https://forum.vcfed.org/index.php?threads/8bi … ga-cards.26866/

The other listing is "IBM 5150 - VGA Cards" on minuszerodegrees:
https://www.minuszerodegrees.net/5150/vga/5150_vga.htm

now I´m thinking about the resistor, as recommended. I´ll see how to do it, before any testing, just in case

Thanks for the info - and good luck! Let us know how it goes.

TheRealAnubis wrote on 2024-09-25, 01:11:

Thanks for the info - and good luck! Let us know how it goes.

well, mod v2 done. I think I can do it better, with the resistor taking up less space, bending its leg the other way around.
i put a 1K resistor.
will that be too much?
or should I put a smaller one, say around 500 ohm to 800 ohm? i first used ~700 ohm, but think it better and switched to 1K
anyway, next come testing...

Your testing should let you know the best value - still looking good!