Which is the exact keyboard sequence to switch an Acer Aspire 5920G to boot from CD?

Which is the exact keyboard-time sequence to switch an Acer Aspire 5920G to boot from CD instead of HDD? I need to be guided like a blind. Let me explain.

Maybe it has been a random event, by the way after a Windows update the Acer Aspire 5920G laptop of my friend has lost its capability to display anything on screen, both on builtin screen and on external monitor from VGA.

In fact, there's no way to see anything of what's happening, because from the moment you turn it on to when you turn it off, nothing is displayed. Bios loading and bootstrap included.

The last attempt that I would like to try before opening the case is to boot it with a Linux live CD, and replicate the exact same actions that I can do on another PC, in order to load a VNC server or something like that, etc.

So I need someone that can guide me as a blind, when I turn it on, to enter the bios menu and change the boot sequence, choosing CD as the first device wher to boot from.

I need something like this:

- turn it on;
- wait (?) seconds;
- press the (?) key quickly for (?) seconds;
- wait (?) seconds;
- press the (?) key;
- press the (?) key (?) times;
- ...

For this reply, you should obviously have access to an Acer Aspire 5920G laptop.