The Patch Since this patch is done in Open Firmware you have to boot your iMac with pressed Command-, Option-, O- and F-keys. At the command line prompt you have to enter the lines exactly as they appear in the gray box below (including spaces and quotation marks). _ means you have to press the space bar. return means you have to press the return or enter key. ctrl-c means you have to press the ctrl- and the c-key. 00000000 are eight zeros, not o's! Caution: The command line doesn't interpret international keyboard layouts. If you use a keyboard version other than English you might have to press other keys to achieve the appropriate character. Please note that you won't get any feedback after you enter the 2nd and 3rd line. The line will just appear cleared. That is normal behavior (it's like a text editor that only displays one line so after a carriage return you will be at the next line which will be empty until you type something). Boot Command + Option + O + F 1 nvedit return 2 "_/"_select-dev return 3 00000000_"_graphicoptions"_get-my-property_2drop_! return 4 ctrl-c 5 nvstore return 6 setenv_use-nvramrc?_true return 7 reset-all return The last command will restart your iMac. Now you can connect a second monitor and get monitor spanning.