View Full Version : 286 + EGA card + 5153 = Problems

July 27th, 2011, 08:29 PM
The office DOS box had to be gutted of its hercules card and 5151 monitor for a customer so I took the chance to upgrade it to color. I scavenged a Deico DEGA-S100 8-bit ISA EGA video card and set it to RGB 80x25 mode and plugged an IBM 5153 CGA monitor into it.
The result is I'm seeing text I swear is 40 column or somewhere funky in between ([url=http://home.online.no/~t-gutteb/51531s.jpg]like this though that might actually be 40 column mode (http://artofhacking.com/th99/v/C-D/50009.htm)) and graphics modes are a bit funky. For example if I try booting the DOS 5 install disk 1, the install screen will be partly displayed in 40 column mode, even though the switches are set for 40 column and so fourth.

July 27th, 2011, 08:54 PM
Did you change the BIOS or motherboard DIP switch from MGA to EGA? My AT clone had XT style DIP switches. I think the actual IBM AT had a jumper block that needed changing.

July 27th, 2011, 10:14 PM
Video mode is set within the BIOS (mono, EGA, 40 column, and 80 column). The system will say there is a configuration error if I set it to anything but EGA. I didn't check for jumpers though.

July 28th, 2011, 12:15 AM
The system will say there is a configuration error if I set it to anything but EGA.
That's expected. For a CGA monitor connected to an EGA card:
1. Set motherboard configuration for EGA.
2. Set switches/jumpers on EGA card for CGA mode.

Check that the switches on your EGA card are set correctly. For example, instead of setting OFF/OFF/OFF/ON, you may have set ON/ON/ON/OFF (the opposite).

July 28th, 2011, 09:23 AM
There was a lone jumper on the board marked "MONO" on one side and "COLOR" on the other. I switched the jumper around so now it was in "COLOR" and tried again.
No dice.

*ignore the complaining installer. It's trying to install to A: