Hey guys, My mid 2011 27" iMac is acting up. I've never had an issue until yesterday when out of the use it randomly shut off. I turned it back on, got the "your computer shut off because of an issue" and continued as if nothing happened. 5 minutes later it did it again. Same message when rebooting. Finally it went into kernel panic mode and continuously began to restart and shut off. I was able to run a diagnostics on it and got this message " 4MEM/9/40000000:OX88933898 I found out this was a RAM issue. I upgraded my 4G of RAM by adding 8 more a year ago. I thought perhaps something gave out so did some trial and error and could not figure it out. Now my computer will not get past the white screen with the apple logo and a loading bar. The computer shuts off half way through the loading bar. I also will occasionally get this message I posted below (right before it shuts off). Any advice what this could be? Running in safe mode/running diagnostics will not work anymore.