The upgrade includes the following features:
- New laser write strategies for 8x DVD+R, 4x DVD+R and 4x DVD+RW media.
- The firmware update will NOT allow the DVD300 drive to write at 8x speeds. The DVD300's maximum recording speed is 4x no matter what recordable DVD media is utilized.
- Further support of black CD-R media.
- Improvement in readability of certain DVD+RW media.
- Improved strategies to increase the number of writes to DVD+RW and CD-RW media.
- Other general errors resolved.
Before Running the Update:
The RecordNow software included on the DVD300 installation disc must be installed for the firmware update to operate successfully. Install RecordNow before running this update.
DVD300e Owners: The DVD300e must be attached to a USB 1.1 or USB 2.0 port during the upgrade process. The firmware update will not function correctly if the DVD300e is on an IEEE-1394 port. After the firmware update, the DVD300e can be re-attached to the IEEE-1394 port.
Instructions:
Download the dvd300n_300.exe file to the computer containing the DVD300 drive. Once the file is fully downloaded, double-click the dvd300n_300.exe file to install and initiate the firmware update. Follow the on-screen directions to complete the DVD300 firmware update.
Reminder:
The DVD300 must have the power cycled off after the firmware update. Reset the DVD300i by shutting down and turning off the computer. Reset the DVD300e by shutting down the computer and manually unplugging, then re-plugging in the power cable into the back of the drive. Restart the computer after power has been cycled. Failure to cycle power may result in the DVD300 temporarily malfunctioning.
Not sure which firmware to download? | 
HP DVD Writer dvd300i Firmware 3.00 (300n drive version)