You've got to be willing to learn how to do these things..... this may be something you want to farm out to one of your friends who is computer-experienced.
There are layers upon layers to learn and it is not all intuitive. You need to find the latest BIOS for your workstation via a search on Google for Z400 drivers, and then enter your OS type, and then download the latest, and then run the installer, and then choose to update from within the OS type you have (32 or 64 bit). There is a better way called updating BIOS from within BIOS, but do you know how to get into BIOS? Have you got your boot block date? Do you have 4 or 6 memory slots?