SVGA cable screwed...
Customer excuse: "It didn't fit tight enough so I used a screwdriver to tighten the screws that held it in place." Except the monitor still reported no signal, so I unscrewed the plug to test the cable. That's when I noticed that all the pins had been crushed into a mangled & tangled heap in the bottom of the plug. Funny how that tends to happen when it's not an SVGA port you're screwing it into... *Sigh*