There are so many different revisions and versions of the Firmware for this drive I will try and help to explain them to help you choose the correct version for your needs
There are basically 3 different versions about:

OFFICIAL
This firmware is released by Pioneer and is unmodified and is RPC2. RPC2 means the drive is region locked and the region can only be changed up to 5 times until it is permanently locked on the last changed to region.

RPC1
This firmware has been modified to remove the region lock and the drive is region free the functionality of the drive should not have been changed.

2x for All
This hacked firmware allows burning at 2x on all media. Be warned the quality of the burn is inconsistent at 2x and is dependant on the individual drive and media and some programs will only write at 2x with this firmware irrespective of the settings.

FIRMWARE REVISIONS
1.55 Official firmware, Problems with burning some of the newer media needs upgrade

1.65 Official firmware upgrade needed for 2x writing on certain media

1.68 Official firmware this enabled 2x writing on certain media. Probably the best all round firmware

1.80 Official firmware supposed to give problems with PS2 games

1.90 Official firmware upgrade released by Pioneer. According to Pioneer this upgrade is needed to fix the bug of possible laser burnout when 4x media is inserted.
This is probably the last firmware that Poineer will bring out for this drive

Some of these firmwares have also been modified to RPC1 and 2x for All

Thanks to GRADIUS, NIL & BATTOUSAI of the Firmware Forum
All the firmwares have been packaged so as to enable easy upgrades.

CAUTION
The 2x firmwares give trouble with some burning programs.
For example if you want to burn at 1x it burns at 2x.
Nero latest version works ok with the 2x speed firmwares.

Lots of 1x cheap media are not readable in lots of players if you burn at 2x.
Also lots of 2x non-certified makes unreliable disks.
Especially the outer edge of the disks will show data errors.

UPGRADING THE FIRMWARE
Upgrades are available here. Each firmware upgrade is in zip file and all the necessary files are included. just unzip all the files into a single folder and from within Windows open the folder and run the UPGRADE.BAT batch file to flash the drive.
This will work when upgrading or downgrading from 1.90 or below.

DOWNGRADE from 1.90
In most cases this can be done the same as above but in the odd case the hacked UPGDVD.EXE is needed.
Just select the required firmware unzip it into a single folder add the UPGDVDHACK.EXE into the same folder and run it. Be warned it can take up to 1 hour or longer to find the key before it flashes the drive.

To avoid unnecessary problems whilst flashing the drive it is suggested that the drive is connected to the secondary IDE controller and no special IDE controller drivers are installed. Drives connected to Raid controllers have been known not to respond as required.

UPGRADE PROBLEMS
The following problems have been reported when trying to upgrade:

Q) I waited 45 minutes for UPGDVDHACK.EXE to find the key to flash my drive. It started at Key0: 0000h, Key1: 0000h, and went through all the key1's and then Key0 changed to 0001h and key1 started to go through again from the start. As nobody has even mentioned key0 changing value, I decided to take the plunge and reboot.
Drive was redetected, but it is still 1.33?
A) If using Windows XP, after uninstalling the VIA bus master IDE controller in device manager try rebooting. WinXP should re-install the driver and it should work fine now first time.

Q) I get this problem: CPU usages gets to 100% when burning.
A) Put your A03 in to Ultra DMA mode

If the process takes longer than 15 minutes, here are some suggestions for people who are having problems:

1) Make sure you aren't using any bus mastered drivers other than the ones that Windows installs for you. So that means any Intel or VIA bus master drivers you might have installed should be uninstalled before flashing.
2) Hook your drive up as the only device on the IDE channel you are using. (Probably not totally necessary for everyone, but at least it can be eliminated as a problem).
3) Make sure no programs you are using are trying to access your DVD-r drive at the same time.

Thanks to Flash for this review.

Added:  Thursday, December 05, 2002
Reviewer:  Flash

hits: 7033