I worked in a state gov't agency as a temp, twice, in the same department. Several of us had shared access to a PC that let us log-into a special terminal program and read records on some mainframe someplace. That PC had a 233-MHz cpu, I'll assume single-core. At that time, it ran Windows NT 4.0, and it had been patched to use a USB mouse. But we didn't rate an optical mouse, so someone would come in twice a day with a tote of cleaning supplies and clean the mouse ball.

After September 11, 2001, somebody came in from the federal government and ordered Windows XP to be the minimum OS for some security issue. The person who had to update that system said a 233 MHz machine was too-slow for XP, and she didn't have a replacement computer, she was already short on computers.

The next time I saw it, it was running XP.