WWhen I purchased it, it ran fine.. I set it up as a new user, logged into my iTunes account and all that, it prompted me to update to yosemite so I did.. It worked fine for about 2 months and then it started turning off randomly, only like once a day. Then it started getting progressively worse.. Sometimes I can even keep it on long enough for it to stop making the startup chime noise. But it will go through a stage that it will stay on for hours but then go back to shutting down all the time..
i Had the usual apps eg. Photoshop, premier, spotify. The only app I every got to alter the computer was called nosleep, I got it from the App Store and it stops the computer going into sleep so I can download things without them stopping.
I Formatted to drive to see if it was software or hardware so there's nothing on it, now when I restart the computer I have to hold command + R and it goes into Internet recovery mode for about 10 minutes, once past that I have to download Mavericks (only option) and the computer never makes it through that, it turns off and I have to do it all over again.
Very annoying.