Monitor Serial Number CN-OXTXXK-72872-49N-CWLL
OSX Yosemite 10.10.4 Macbook Pro 13inch mid 2012
I have a Dell U2413F monitor connected to a Macbook Pro with a display port to miniDP cable. After two months of use without any issues, the monitor, when connected to my Macbook, freezes the computer. The Macbook screen goes dark and the Dell has the floating message saying that it’s entering power save mode. I have to perform a forced shutdown of the Macbook and restart it. Connecting the Dell monitor at any point, computer on, off, asleep, causes the Mac to freeze.
I’ve also started the Mac in safe mode and connected the Dell monitor. The first two times I did this the monitor worked. Now when I do it the computer itself works (connecting or disconnecting the monitor doesn’t freeze the computer) but the monitor stays black with a warning that it is not receiving a signal from the computer. In system preferences, under display, it shows that the Dell monitor is connected (the computer can see the monitor) but the monitor itself remains dark.
Suggestions?