said by fish23 :
if both optical drives go bad,will the computer still boot up?
If you are trying to boot from only an optical drive (check your BIOS CMOS settings to find out), the answer would be no.
Sample CDROM only boot setting
If not, then the answer could still depend upon the settings in your CMOS. Some computers have BIOS options to halt on any error. If you have that option selected, then the computer might halt upon detecting the optical drive failure.
Sample halt on error setting