Unfortunately, no.
The PCs in the Library are all-in-one computer/monitors, which, by design are configured to not allow usage as a monitor only.
Furthermore, for security reasons, the computers in the library have had a physical shield installed to prevent external cables being both removed and able to be plugged in to the back of most of the machines.
The Library do have large screens and HDMI cables installed in the group study rooms that you are able to plug your laptop into, and use both screens. Which can be handy, we know, when you are dealing with many tabs and a lot of work. You can book a room ahead of visiting the CDU Library on the CDU Library website, here: libcal.cdu.edu.au/spaces.
