As you can see it's an early card. It has less resistors and a black, widened bracket.
But has anyone ever seen a card with that many botch wires on the back of it?
World's foremost 486 enjoyer.
Goes with the early IBM PC the one with 5 slot motherboard. Not XT.
Cheers,
Great Northern aka Canada.
I have one like that. Same P/N, wiring job, and resistor count/values at the composite output stage (one less resistor than other known 'early-type' CGA boards... although I don't think there's much of a difference in the output).
However mine has the later, narrower XT-type bracket:
The board itself is a bit different as well, although all I can see at a first glance is the extra text on the back next to the edge connector.
Hmm. I'm trying to make sense of the date codes on the chips. Your U33 (what chip is that?) says 82-something, while mine says 8141. However, my board has a bunch of 82xx date codes that exceed the ones on yours. Latest one I can find is 8227.
Your MC6845P says 8218 whereas mine says 8216.
I'm going to say both of these boards were manufactured mid-1982.
But why the botch wiring? I wonder what the earliest boards, manufactured in 1981, looked like.
World's foremost 486 enjoyer.
Yeah, it's hard to tell based on the date codes alone - they probably mixed-and-matched components from whatever batches they had lying around (U33 is the character ROM).
Mid-'82 sounds about right, and my card also has that '8212' text on the back, but the narrow XT-type bracket must have come later since the 5160 was introduced in March '83. I assume that mine just sat in the inventory until it was converted later to be sold as part of an XT.
On VCFED there are pics of what the poster calls a "very early IBM CGA with date 44/81": https://forum.vcfed.org/index.php?threads/ano … restored.70436/. Unfortunately most of the numbers there aren't really visible, but it has even more bodge wiring (an extra red wire on the left). The early MDA in that post has that stuff too.
