Thanks for all the suggestions. As I was poking around with my breadboard leads to check everything per your advice (resistance, connection of pins to the shield, etc.) I realized that two of the pins on the PS/2 side of the faulty adapter (the DAT and unconnected pin 2) were much less "tight" than …

I have a PS/2 keyboard attached to a Belkin Omniview KVM (F1D104-OSD) that I'm trying to use with two machines—a 486 and a Socket 7 motherboard (both have AT keyboard connectors). I have two AT to PS/2 (DIN to mini-DIN) adapters, which look identical but came from two different sources. Both …

Thank you everyone, that's very helpful. I was hoping this was intentionally done and some kind of mod (optimistic thinking), but you're right there's quite a bit of other damage in this area as well. I'll look into returning it.

I recently got my hands on a Sound Blaster 16 (CT2950) which seems to have had some modifications made—the two leads (C1, C3) off a component in the top-left corner have been cut off, and the resistor at C2 also seems to have been removed. Can anyone help me identify the component that's been …