It passes the extended hardware diagnostics, boots and runs fine. But when something plugs into the USB or Firewire port, the screen gets partial blocks of wiggly lines in them. The mouse still moves, on screen items don't work, keyboard eject works for while and finally the unit is unresponsive. Reboot and its fine until something like an external drive or memory stick is plugged in. It has a couple of things plugged in already like a bluetooth usb stick, keyboard and mouse.