It's still trying to boot from the hard drive.
There must be one key that you keep tapping at startup to access the boot menu, so you can select to boot from USB, CDROM, or what have you.
Try some of the others I suggested above.
i can enter the boot menu and i can choose it to boot from cd drive but when i save and exit the boot menu it restarts and when it comes back on it shows nothing on the monitor.