The screen has a purplish blemish in the very center of the screen.  The SD card reader does not operate.  The back of the case (upper right) was not closed (although it was easy to snap back together).For a refurbished unit advertised as used but in excellent condition it was certainly not inspected very well!I only use this computer to run a CNC machine so I can overlook these defects but others may not be able to do so.