My late 2011 MacBook Pro 4 gig RAM is running very slowly, crashing very often. Repaired permissions, repaired disc, updated to Mavericks, uninstalled Blackberry Desktop. Can only run one app at a time, barely.

Question

Activity monitor shows RAM usage at between 3 and 3.95 most of the time, even with no apps running.  Hard drive has plenty of free space.  Chrome crashes it the most, but any time I run more than two apps at a time, it crashes.  It cannot ever complete a Time Machine backup.  That leaves it dead in the water after a few minutes.  When I say crash, I mean totally unresponsive, even when left alone for hours.  Only a hard reset works.  Then, it is hit or miss when it comes to rebooting.  Often, it crashes at the startup login screen, and often it doesn't even make it that far.  Sometimes, the computer spontaneously restarts itself.  I've looked at the forums, and tried everything that I've seen suggested. I've left it alone overnight, hoping that it was just indexing, but no dice. I even used the sudo purge command once.  That cleared up some RAM for a moment, but didn't affect the performance issues.  I am aware that the RAM usage may have nothing to do with it, but that's the only clue I have.  It is a miracle that I'm even able to finish typing this message, since right now I have Safari and Mail open at the same time!  I've turned off Drop Box.  Every application loads painfully slowly, and then any activity, including typing, is often interrupted by the spinning pinwheel of death.  Sometimes, the problem resolves for a few minutes, and then returns with a vengance.  Help!

Answer 1

Activity monitor shows RAM usage at between 3 and 3.95 most of the time, even with no apps running.  Hard drive has plenty of free space.  Chrome crashes it the most, but any time I run more than two apps at a time, it crashes.  It cannot ever complete a Time Machine backup.  That leaves it dead in the water after a few minutes.  When I say crash, I mean totally unresponsive, even when left alone for hours.  Only a hard reset works.  Then, it is hit or miss when it comes to rebooting.  Often, it crashes at the startup login screen, and often it doesn't even make it that far.  Sometimes, the computer spontaneously restarts itself.  I've looked at the forums, and tried everything that I've seen suggested. I've left it alone overnight, hoping that it was just indexing, but no dice. I even used the sudo purge command once.  That cleared up some RAM for a moment, but didn't affect the performance issues.  I am aware that the RAM usage may have nothing to do with it, but that's the only clue I have.  It is a miracle that I'm even able to finish typing this message, since right now I have Safari and Mail open at the same time!  I've turned off Drop Box.  Every application loads painfully slowly, and then any activity, including typing, is often interrupted by the spinning pinwheel of death.  Sometimes, the problem resolves for a few minutes, and then returns with a vengance.  Help!