For what I'm using the computer for, which is in a home audio recording situation, it's decent.It's not used often, but has been running well since it was purchased - just over 90 days ago - up until a few days ago;It started randomly powering off.  The last time it did so, it kept trying to reboot but would stop and try again and again until a pre-boot error message appeared: "Error - Memory configured incorrectly".  This happened a few times before I shut it down, opened it up, only to find that this refurbisher used THREE different brands of memory, and TWO different types/speeds of memory!  I debated giving more stars since the machine itself is okay, but that's pretty a really underhanded, cheap, and weak thing to do.Anyone with even a small amount of computer building literacy knows you don't mix memory like that!Had I known that right off the bat, I would have demanded replacement memory, or sent the unit back.To make sure the computer is reliable and not going to continue shutting down while I'm in the middle of a recording session, I'll need to replace the memory.