The DVD Burner Optiarc AD-7740H is a slimline drive. The Optiarc AD7743 burner adds support for Labelflash but both drives share the same hardware and only differ in firmware. However you should not try to simply flash an Optiarc 7743H firmware on an Optiarc 7740H drive or vice versa. This will NOT work.
The following firmwares are available for download here:
Overview on the used writing strategies