Guys i had the same issues with the balck screen of death ever since i upgraded to lon. I couldnt run any app decently without the system crashing within minutes of opening the app. I checked my hard ware, all fine, i even tried to downgrade, but couldnt do it on a new partition...for some reason lion wouldnt let me install snow leopard on a different partition. I finally went to the genius Bar and the Genius actually did some Permission repairs, went into Disk Utility, clicked on the hard disk and then clicked on Repair permissions. It seemed to work. Now when i sync my iphone in itunes, the system doesnt crash. Still have to do a full stability test, but this is definitely some route to go from what it seems. Ram was fine.
I had one crash later after i started downloading something from the appstore..it crashed the system...seems like the storeagent process which runs in the background isnt compatible with LION...however closing the appstore solved the issue...and my computer has been running with me actively using the system for past two hours. Finally!! Such a simple solution as well
I have a mid 2007 imac with a fresh HD (2 or 3 months old) and I upgraded to Mountain Lion several days ago.
Here is what has happened since:
1) Screen started dropping out (Going Black) but computer seems to be running in the back ground.
2) I read multiple posts...
a. Tried resets (w/ apple care on phone)
b. Disk Repair (w/ apple care on phone)
c. Fresh install of Mountain Lion (w/ apple care on the phone)
d. Tried to download Smart sleep, Fan Control, apps nothing would allow me to use with the opperating system.
3) I gave up, so I tried to use my Time Capsule to revert back to prior version of Lion ( 7/24/12 last back up)
after many hours going into the last bit the screen went back and I had to reboot, then this corrupted my time capsule and gave me an error message. At this point I have so many hours involved I am about ready to .
4) This morning I gave up and put in my Snow Leopard CD and started from fresh.
5) Tonight I was able to access my Time Capsule, thank God but not through the normal back up process with Time Machine. I started to copy over the files to my HD and everything was working and then :::::: BLACK OUT AGAIN :::: this is with SNOW LEOPARD running.
So my questions is now was it really Mountain Lion ? or did Mountain Lion fry my graphics card? I am at a loss, I am so ready to upgrade to a new computer but still waiting on newest release. Oh well time to set up an appointment with a Genius.. I feel everyones pain who maybe experiencing these same issues.
Best of Luck