View Full Version : The PS/2 Display Adapter

Great Hierophant
March 23rd, 2006, 08:06 PM
This is IBM's sole attempt to bring VGA to the PCs. Scott Mueller had one and says it is a full-length 8-bit ISA card that gives full VGA compatibility (and nothing more of course.) He also commented that it has 24KB of ROM (instead of 32KB on more common VGA cards) and also addresses the ROM in a non-standard way. Does anyone have this card? Can anyone post a picture of it so I know what to look for?

March 27th, 2006, 03:04 PM
I think it's going to be fairly rare. Just found out recently (I'm amazed how these facts excape me!) that the VGA system is based on the Inmos G171 chip. I had thought that it was all custom IBM logic. The PS/2 models 25 and 30 also used it, though technically they're not VGA. The only reason I spotted the things (with any recognition) was because I did some investigating into an old PGA-like video card I have made by Vermont Microsystems. It's a dual board, not sure what resolutions/colors it has, at least 400 lines, not sure if it's analog or not though. It has the Inmos G170 chip. Funny, the darned thing works in an old DTK based P166MMX, but not in my PC/AT!! Go figure...
Good luck on your search. I wouldn't mind owning one either.

Terry Yager
March 27th, 2006, 04:29 PM
I have a card here, that I pulled fron an 8-bit slot, so I'm pretty sure it works that way. It's interesting, because it looks exactly like an ATI VGA Wonder, might even be a re-badge, but it's a no-name clone (chips have been sanded down). If ya wanna try your luck with it, cost of shipping...


March 29th, 2006, 04:06 PM
I have to correct myself oi. The G170 series are not crt controllers. They are ramdac's. They store the color info (the ram part) and they convert this digital info to analog. Just to set the story strait.