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 PAL or NTSC-U models. 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)
These systems can be hard to find in America, and are definitely more common in Japan. Here, the motherboard runs hotter, warranting a more robust cooling solution. Some say they 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 code on the sticker.
Playing burned games is possible on a VA0, and are capable of running DreamShell.
ODE replacements for VA0s require the 5 volt resistor networks on the motherboard to be replaced, as ODEs run at 3.3 volts. If not done, both the VA0 console and ODE risk getting damaged. After the ODE is installed, the VA0's 5.5 volt GD-ROM drive can't be reused given the change in the motherboard's voltage, but a VA1's GD-ROM drive can because it runs at 3.3 volts like ODEs do.
“VA1” (1999-2000)
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.
These can play burned games, run DreamShell and are capable of running ODE replacements with relative ease. No modchips, major modifications, motherboard alterations, etc. are required on VA1s. To identify, look at the bottom of the system; look for the circled “1” to the left of the NTSC-U code on the sticker.
Given how common they are, VA1s tend to be the easiest to find replacement drives for.
“VA2” (October-December 2000)
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 code on the sticker.
For this revision, the drive microcontroller is now relocated and integrated with 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 difficult. Despite these notable differences, the VA2 uses the same laser disc drive as the VA0/VA1. Instead of connecting to a daughterboard as in previous revisions, the disc drive connects directly to the motherboard in the VA2.
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 disc drive's laser eye connected to the VA2's orange ribbon cable. The ribbon cable itself is hard to find replacements for if it gets damaged, but the disc drive is easier to find as it is essentially universal with all Dreamcast revisions.
VA2s made in October and early November 2000 can play MIL-CDs, burned games and DreamShell natively because the VA1's BIOS (v.1.01d) was used on them. Al Balog was able to confirm this, as well as other lost or unknown information regarding the VA2 revision.
Starting in batches made in late November and December 2000, the BIOS has been changed to v1.022 to prevent the loading of MIL-CDs and burned 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, being labeled "MPR-23588", but it didn't start being used in motherboards until a month later.
For late November and December VA2 units, they do not support playing MIL-CDs, burned games or DreamShell unless the console has a region free BIOS modification, or if the VA2 motherboard and drive (both of them) are replaced with those from a VA1's.
As of 2024 there is no ODE replacement for the VA2 revisions and their motherboards, regardless of the BIOS type and batch date.
In March 2024, Al Balog was able to expose a GD-ROM vulnerability in the late November and December VA2 units. The v1.022 BIOS does not have any security against burned GD-ROM games or GDI dumped games. The security only applies to MIL-CD and CDI file games. Theoretically, if a manufacturer were to make a ODE for the VA2's drive controller ports, console that have the v1.022 BIOS would have no problems reading games from the ODE, as long as the games in question are in GDI format.
No matter the unit's date, the only possible way for a VA2 to run a ODE is to replace the VA2's motherboard with a VA1 motherboard. It has been confirmed that a VA1 motherboard will fit into a VA2 console shell, with the controller ports and PSU being universal for all motherboard revisions. The VA0 motherboard has a different fan placement, making it harder to fit into a VA2 shell. 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, which makes a motherboard swap possible.
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 special Japanese editions, like the Sakura Wars console, were made in Japan in the first quarter of 2001. The VA2s were the last Dreamcast units before discontinuation was officially announced on March 31, 2001.
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.
UD: Made in Japan by UGO DENSHI. Manufactured VA0s, VA1s and Japanese special edition VA2s.
AE: Made in Japan by ASAHI Electronics Co., Ltd. Manufactured VA0s, VA1s and Japanese special edition VA2s.
TK: Made in Japan by T. TKR. Manufactured VA0s and VA1s.
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://web.archive.org/web/20240121210335/https://www.gamerlifestore.com/cdn/shop/products/[email protected]?v=1632769695 (picture of Model 2 parts, shows the Model 2 motherboard having an integrated drive controller & having a unique GD-ROM drive that attaches via ribbon cable)
https://web.archive.org/web/20240121210345/http://web.archive.org/screenshot/https://www.gamerlifestore.com/products/sega-dreamcast-console-model-2 (screenshot archive of the sales page the Model 2 parts & motherboard originally came from)
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/2024/02/04/va2_dreamcast_a_sa_made_in_china_kepe_2000_december (confirmation of VA2 unit info with pictures, examination of BIOS, flashrom, chips, date batch capability, etc.)
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)