Last night, the iMac wouldn’t come back from the screen lock, it would just show an arrow but without asking for the username and password. Trying to access it from the network didn’t work either, so I power cycled it.
It has not come back. I have contacted an Apple agent with the chat app (fortunately, I bought the AppleCare Protection plan), and after following some diagnostic procedures (resetting the PRAM, the NVRAM and the SMU) he has finally suggested to contact an authorized Apple Center :( Looks like the power supply or the display board aren’t working properly.
I had heard some older revisions of the iMac had power supply problems, but I thought this was already resolved. Let’s expect this doesn’t take too long to fix. Why oh why had this to occur in the week of the finals?