Chosen Solution
Computer: Mid-2011 iMac 27" 3.4ghz i7, 2gb video, 16g ram, 1tb hdd + 256 ssd Initial problem: While working, all data on screen got warpy for 1/100th of a second then went black. Attempts to reboot were met with grey screen past Mac “boom”. Startup menu for disc selection (option key) works, but no system boots, no recovery boots (internal, web, usb key). They all hang @ loading bar or a grey screen. Originally thought the SSD had gone bad, but was able (am still able) to TDM (target disk mode) into the computer via Firewire to my MBP. All files work fine, I can even boot from the SSD in the iMac ON my MBP and use the OS. All files on both drives are available and read and write fine. I had thought that my logicboard was bad, BUT usb/FW connections, wifi & wired connections work fine (able to access internet for network recovery boot though unsuccessful) - does this invalidate that? Is my GPU likely gone, not letting me boot past a certain part of startup? It would be awesome to get this machine up and running, but I’d like to save $$ where possible and not order both a new GPU & logic board/CPU. Internet diagnosis?
Don’t panic. probable gnu issue. hookup an external monitor. boot in Safe mode holdinding down shift. key on status and report finding. traveling so reply may be slow and abbreviated till next Tuesday UPDATE 10/15/17 Now thatbwe’re both back home let’s see if we can get it diagnosed. My initial though was that it’s a GPU issues. See if this old recall firs your serial number and your symptoms: https://9to5mac.com/2013/08/16/apple-ope…
