In order to make the Dreamcast region free you require a new BIOS.

You can use

The best BIOS I find is called Japanese Cake. You can find the downloads on that site, or here. The new website is also here.

Here is the latest v1.032 BIOS from Japanese Cake.

Use the T48 programmer to program a blank BIOS chip if you have one, or just buy a Japanese Cake BIOS directly from us.

Start by powering on the Dreamcast and measuring the voltage on pin 23 (VCC) of the BIOS to confirm if you need the 3.3V or 5V BIOS.

The original BIOS for !RESET and !WE are disconnected, but on the new BIOS installs, these two pins need wiring up.

If your BIOS is 3.3V, you need this bios.

If your BIOS is 5V, you need this bios.

Before starting, use aluminium tape to cover the plastic connector so you do not melt it during work.

Hot air the old BIOS off, and solder the new BIOS in place.

Finally, join the !RESET (pin 1) to VCC (pin 23) so that the BIOS is not in reset.

Add one more wire, from !WE (pin 44, low for Write Enable) to B14 of the GD ROM connector (G1 !WRITE), so that if you want to re-flash the BIOS using DreamShell or similar you can.

In order to test the console, you will need the fan connected, and the GD ROM or GDEmu connected otherwise it will not boot.

If testing while open, make sure to prop up or hold the GD ROM / GDEmu up level so it is not bending downwards, as the connector between the motherboard and GD ROM is really poor and needs to be straight and level, otherwise nothing will boot.

If you have installed one of our BIOS chips, once started, go to Settings on the Dreamcast and press Start to open up the custom settings menu to change things like logo color, bypassing SEGA license and other options.

Even if you change the BIOS to a region free BIOS, your Dreamcast will still be set to its original region.

This can cause issues with video output if say you install a region free BIOS into a Japanese console, and play UK games. The video will be off center, greyscale or flickering.

The region is saved in Flash Mask ROM, make sure to follow the Region Change guide to change the region.

On top of a region free BIOS, you also need to locate the test pad labelled R422 and bridge it. This tells the Dreamcast to listen to the games region (50/60Hz) and switch to that frequency.

If you do not bridge this, some games will run shifted down on the screen or black and white.

The pad is located near the AV port on the back.