486 is booting monochrome unless monitor off \ VOGONS

486 is booting monochrome unless monitor off

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First post, by thewidow13

Posted on 2012-04-14, 05:53

thewidow13 Offline

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Joined: 2012-04-11, 23:41
Location: United States

One of my 486 pcs is booting into monochrome if I have the monitor it's connected to turned on. If I power it off and boot the pc, the computer boots up fine in vga mode. If I have the monitor on and boot up, most games except a select few are in monochrome and msd.exe reports it as monochrome. I've looked all throughout bios and can't find any pertinent settings. What would cause something like this?
Specs are i486sx/33, 8mb ram (8x1mb 30 pin simm), sb16 vibra, and an asi vga card (can't remember what brand).

Thanks,
Joe

Reply 1 of 3, by DonutKing

Posted on 2012-04-14, 06:32

DonutKing Offline

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Location: Australia

What sort of monitor are you using?

Originally Pin 12 was used as a Monitor ID pin, it was grounded in Monochrome monitors and not connected in colour monitors. Later on after DDC (Display Data Channel) came along, the monitor ID pins were used to transfer data between the monitor and video card. Its possible you have an older video card that is not DDC aware and your newer monitor with DDC is getting detected as mono because this line is grounded on boot.
Alternatively, you might have a broken wire in the cable and its shorting out on the grounded metal braid inside the cable.

If you are squeamish, don't prod the beach rubble.

Reply 2 of 3, by thewidow13

Posted on 2012-04-15, 00:39

thewidow13 Offline

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Joined: 2012-04-11, 23:41
Location: United States

Thanks for the reply. The monitor is an old crt Trinitron Multiscan 200sf (can't stand DOS gaming on an LCD!). Could I just break that pin off on the vga connector for the monitor so that it isn't grounded?

Thanks,
Joe