Comment by electroly

This hasn't mattered in 20 years for me personally, but in 2003 I killed connectivity to a bunch of Siemens 505-CP2572 PLC ethernet cards by switching a hub from 10Mbps to 100Mbps mode. The button was right there, and even back then I assumed there wouldn't be anything requiring 10Mbps any more. The computers were fine but the PLCs were not. These things are still in use in production manufacturing facilities out there.