We got a new monitor today for one of our pairing work­sta­tions. At 2560x1600, it was higher resolution than its pre­de­ces­sor. I dis­con­nect­ed the DVI cable from the old monitor, leaving it connected to one of the video ports on the computer, and connected it to the new monitor. All I could see was static and noise on the screen. After trying a variety of other things, I eventually thought to use the DVI cable that came with the new monitor. It worked!

I had assumed that all DVI cables were in­ter­change­able. Reading the Wikipedia article, I see that at higher res­o­lu­tions, dual link is needed. I hadn’t known such a thing existed.