After booting up the login screen shows two separate login forms (i.e. typing in one doesn't show up in the other), and I can move between them with my mouse in a logical side-by-side manner. But after logging in the monitors go into "duplicate" mode, i.e. both show the same content. I can override this behaviour using xrandr but I wonder why I can't just keep the original configuration used in the login screen where it was working.
Both monitors are on one nvidia geforce 210 PCI card.