Dreamcast:Dreamcast Model Differences
Page content & researching taken from io55.net's Dreamcast page and albalog.blog.hu's posts (specific pages in references) with permission, in collaboration.
There is only one Dreamcast model, but three revisions are within it.
Models + Revisions
Models are arranged chronologically. Revisions are underneath their respective model.
Disclaimer for Japanese Dreamcasts only:
Japanese Dreamcasts have markings that are different than NTSC-U or PAL units. They don't have the typical number at the bottom with the circle around it denoting if it is a VA0, VA1 or VA2.
The best listing on the net currently explaining differences between Japanese models is located here. Ultimately the data plate on the BOTTOM of the Dreamcast is still the best spot to determine if it will work with an ODE but it is done differently than NTSC-U and PAL units.
https://web.archive.org/web/20210530160307/http://users.skynet.be/t_chan/dc/mylist.htm
Dreamcast (1998 - 2001)
The only model of this console. Up front are four controller ports, while the top has the drive, plus power & drive door buttons. The left side has nothing, and the right side has the large extension port, by default taken up by the Dreamcast’s 56k modem (which is removable). On the back is the AC out, AV out, the line/ethernet port (depending on the peripheral installed in the extension port), and a serial port meant for link cables. There is nothing on the bottom except for the model number label and regulatory information. Later revisions have a supposedly better drive, but to the detriment of installing certain ODEs. All Dreamcasts have certain issues between the power supply board connection, but this can be fixed with just a clean, or a soldering/replacement job.
VA0 (1998 - 1999)
General info:
These systems can be hard to find in North America and especially in PAL countries, and are definitely more common in Japan. Some have debated if PAL VA0s exist, but photos of one manufactured in April 1999 are available. Here, the motherboard runs hotter, warranting a more robust cooling solution with steel pipes connected to a plate above the two CPUs. Some say the VA0s have a superior build quality.
To identify, look at the bottom of the system; look for circled 0 to the left of the NTSC-U or PAL code on the sticker.
BIOS and compatibility info:
Playing burned games is possible on a VA0, and this revision is capable of running DreamShell. The VA0 uses the BIOS v1.004 with chip MPR-21068, which has full MIL-CD and CDI disc image format support.
ODE status:
As of 2024, the only ODE known to work natively with the VA0 without any soldering is Terraonion's MODE. Similar to the VA1, the VA0 has a 50 pin BTB connector.
GDEMU for VA0s require the 5 volt resistor networks on the motherboard to be replaced, as GDEMU run at 3.3 volts. If not done, both the VA0 console and GDEMU risk getting damaged. After it is installed, the VA0's 5 volt GD-ROM daughterboard can't be reused given the change in the motherboard's voltage, but a VA1's GD-ROM daughterboard can because it runs at 3.3 volts like GDEMUs do.
Alternatively, the VA0's motherboard can be replaced with that of a VA1's for ODE devices to work.
VA1 (1999 - 2000)
General info:
The vast majority of NTSC-U and PAL Dreamcasts are of the VA1 revision, also considered by many as being the most user-friendly revision for the average user.
To identify, look at the bottom of the system; look for the circled 1 to the left of the NTSC-U or PAL code on the sticker.
BIOS and compatibility info:
Playing burned games is possible on a VA1, and this revision is capable of running DreamShell. The VA1 uses the BIOS v1.01d with chip MPR-21931, having full MIL-CD and CDI disc image format support.
ODE status:
VA1s are capable of running ODE replacements with relative ease, thanks to the VA1 having a 50 pin BTB connector as well as running at 3.3 volts. Also in part due to its BIOS, no modchips, major modifications, motherboard alterations, etc. are required on VA1s.
Repairs:
Given how common they are, VA1s tend to be the easiest to find replacement parts for.
Disc drives on a VA1 run from a 3.3 volt daughterboard, and a 5 volt daughterboard from a VA0 is not recommended to be used as a replacement part, as it could cause damage the VA1 console. However, the disc drive with the laser assembly itself is swappable between all Dreamcast revisions.
With the exceptions of the VA1's daughterboard and the motherboard, every other part of the VA1 (disc drive, PSU, controller port, console shell, etc.) can be swapped with the VA2.
VA2 (October - December 2000)
General info:
Quite rare, but not as rare as the VA0s, although this is not confirmed. To identify, look at the bottom of the system; look for the circled 2 to the left of the NTSC-U or PAL code on the sticker.
For this revision, the drive microcontroller is now relocated and integrated into the motherboard itself, thus it has no GD-ROM daughterboard like the VA0 and VA1. The VA2's motherboard is hard-coded with driver software completely different than the VA0/VA1, making ODE development for this revision difficult.
The VA2 uses a long, detachable orange ribbon cable that has a different shape than the VA0/VA1. However, both ends of this cable have the same 16-pin slot to connect the laser eye mechanism to the motherboard. Also, the disc drive switch (which allows discs to be played when the Dreamcast lid is closed) connects directly to the VA2's motherboard via a detachable wire. This is different than the VA0/VA1 disc drive switch, where it is physically mounted onto the daughterboard. Both the VA2's ribbon cable and disc drive switch are rare parts, and are unique to the VA2 revision only.
Despite these notable differences, the VA2 uses the same laser disc drive as the VA0/VA1. Instead of connecting to slots on a daughterboard as in previous revisions, the disc drive connects directly to the motherboard. Slots on the VA0/VA1 daughterboard were simply relocated to the motherboard of the VA2.
The VA2s are made in China (either WK or SA initials), being made from October to December 2000 in North America and PAL regions. Some Japanese consoles that were made in Japan (made by ASAHI Electronics or Ugo Denshi) lasted into first quarter of 2001. The VA2s were the last Dreamcast units made before discontinuation was officially announced on March 31, 2001.
ODE status:
As of December 2024, there is no ODE for any batch of the VA2, although the upcoming Phøde ODE claims to have a working QSB prototype (quick solder board) to link the Phøde to the VA2's motherboard.
BIOS and compatibility info:
VA2s made in October and early November 2000 can play MIL-CDs, burned games and DreamShell natively, given that BIOS v.1.01d was used on them (chip labeled MPR-21931), the same one used on the VA1. These early batches of the VA2 are also known by their nickname VA2.1 because of this retained compatibility feature.
Starting in batches made in late November 2000, the BIOS has been changed to v1.022 (chip labeled MPR-23588) to prevent the loading of MIL-CDs and burned CD games, which also prevents DreamShell from being used (as it uses a boot MIL-CD to start the device).
The chip for the v1.022 BIOS was mass produced during the later half of October, but it didn't start being used in motherboards until a month later in late November. This BIOS does not have any security against burned GD-ROM games or GDI dumped games. Burned GD-ROMs are extremely rare, and are typically associated with developer prototype game discs. The updated BIOS security only applies to MIL-CD and CDI file games.
The only two solutions to solve this issue on the later batches is to have a region free BIOS modification done via soldering, or replace the motherboard with that of an earlier BIOS.
No matter the unit's date or BIOS, the only possible way for a VA2 to run a ODE is to replace the VA2's motherboard with a VA1 motherboard. However, the VA2's protective metal blocks the VA1 motherboard's GD-ROM slot, thus requiring the protective metal to be replaced with a VA1's metal. Alternatively, the VA2's metal can be trimmed to make room for the GD-ROM slot, but it is risky considering the VA2's metal has two attached layers, making it thick to cut. The console shells and heatsink plates of the VA1's and VA2's are built exactly the same, allowing a motherboard swap to be done.
While technically possible, the VA0 motherboard (given it has a proper voltage ODE on it) can be used, but it has a different fan placement, making it harder to fit into a VA2 shell. This issue can be potentially fixed by trimming certain plastic holders on the bottom interior of the VA2 shell.
Repairs:
The VA2 can have its disc drive replaced with that of a VA0/VA1. First, it needs to be separated from the GD-ROM daughterboard and steel casing, and the ribbon cable detached from the laser eye mechanism. Then, the VA0/VA1 disc drive's two JST connectors (with the red/white/black wires) need to be plugged into the VA2's motherboard, and the back slot of the disc drive's laser eye connected to the VA2's orange ribbon cable.
The VA2's ribbon cable and disc drive switch are hard to find replacements for if they get damaged, but the disc drive itself is easier to find as it is universal with all Dreamcast revisions.
PSUs, controller ports, modems and heatsink plates for the VA2 are same as the VA0/VA1, making these parts universal as well.
As for the console shell and fan, the VA2's is the same as the VA1. However, the VA2's fan placement is different than the VA0, thus a slightly different bottom shell than the VA0.
Manufacturer Information + Initials Guide
North American Dreamcasts have initials on the bottom label of the machine, indicating the country it was made in and the manufacturer it originated from. Japanese Dreamcasts list the full name of the manufacturer with the country it was made in. PAL Dreamcasts don't have the manufacturer information on the bottom label, only the country of origin.
WK: Made in China by Wong's Kong King Int'l (Holdings) Ltd. Manufactured VA0s, VA1s and VA2s. Only manufacturer that made the SEGA Sports Edition Dreamcast.
SA: Made in China, unknown manufacturer. Manufactured only VA2s.
SD: Made in Japan by Sanwa Denki Kogyo Co., Ltd. Manufactured VA0s and VA1s.
TK: Made in Japan by T. TKR. Manufactured VA0s and VA1s.
UD: Made in Japan by UGO DENSHI. Manufactured VA0s, VA1s (for Japan only) VA2s.
AE: Made in Japan by ASAHI Electronics Co., Ltd. Manufactured VA0s, VA1s and (for Japan only) VA2s.
GS: Made in Indonesia, unknown manufacturer. Manufactured only VA1s.
References
https://dreamcast.wiki/MIL-CD_compatibility
https://www.reddit.com/r/dreamcast/comments/lfhr2z/great_dreamcast_hardware_revision_database/
https://www.reddit.com/r/dreamcast/comments/8zaxni/i_just_found_a_rev_0_ive_read_this_is_the_best/
https://www.youtube.com/watch?v=c3tNCkY3CY4 (ModzvilleUSA! video on running a GDemu on a VA0)
https://www.youtube.com/watch?v=jkz9X5S70FQ (Blaine Locklair video on running a GDemu on a VA1)
https://gdemu.wordpress.com/details/dreamcast-details/
https://gametrog.com/sega-dreamcast-information-specs/
http://www.tankgirl.info/8bit/images/sega/dreamcast/modem.jpg (removed modem, reveals EXT)
https://cdn.shopify.com/s/files/1/0049/8719/1386/products/image_ed7b0f8a-d94a-4749-9ca9-cca916f238f8_500x205.png (sticker on the bottom, showing the circled number for revision)
https://web.archive.org/web/20210518194534/users.skynet.be/t_chan/dc/mylist.htm (in-depth info about the manufacturers & Japanese manufacturer initials)
https://segaretro.org/WKK (WK on made in China batches means Wong's Kong King)
https://albalog.blog.hu/2024/01/24/va2_dreamcast_kiserlet (proof of it being possible to swap the VA2's components with VA1 components to run burned games and/or GDEMU)
https://albalog.blog.hu/2024/03/06/a_titokzatos_sega_dreamcast_va2_revizio_alapos_felfedezese_resz (defeated the GD-ROM security of the late November and December 2000 VA2 units, the BIOS chip only protects against MIL-CD and CDI burned games)
https://mcretro.net/sega-dreamcast-pal-revision-va0/ (proof of PAL VA0 machines existing)