MacBook Pro, Late 2011 2.5Ghz. The Mac works perfectly fine, however, every so often, the Mac simply freezes and doesn't respond. Therefore I turn it off, and when turning it back on weird lines appear.
The Mac loads up and then shuts down again as soon as the loading screen ends. We tried replacing the RAM because we recently had a RAM issue, but that did not fix anything. Has anyone had a similar problem?