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System BIOS


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Category Sega CD
Assets 9
Hits 73,087
Comments 21

Comments (21)


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An official custom-made Mega-CD BIOS made for Sonic Team creative director Kazuyuki Hoshino has recently been found and preserved online!
R7CrazyCanucks Sep 20, 2026 3:31 AM
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in my opinion, both the international and US model 2 songs are fine, but the US model 1 song is less than acceptable. the US ones are vastly trumped visually by the international variants.
LapisLink May 28, 2026 12:57 AM
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how i tile rip bios sprites
ScratcherGames64 Mar 24, 2026 4:39 PM
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sound effects have now been added enjoy!
cycriccizer Jan 3, 2026 11:29 AM
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Also, I've recently obtained a PAL Mega CD II, which makes me really wanna rerip this whole page, so expect some revisions
lucas_mother3 Oct 13, 2025 10:27 AM
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@Logipogironi That's the Sega CDX / Multi-Mega models' BIOS. The only difference I know of is the ver. number saying 2.21 instead of 2.00 or 1.00 but I may be wrong. Look at it on TCRF if needed https://tcrf.net/Sega_CD#BIOS_Versions
lucas_mother3 Sep 23, 2025 12:58 PM
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I remember a “SEGA CD Ver2.21” model but i don’t remember the actual name.
Logipogironi Sep 13, 2025 12:39 PM
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@TotallyNotNess the US Model 2 music is pretty good, in fact, it's my favorite of all of these.
LapisLink Jul 13, 2025 3:21 PM *
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It's sad that the USA Models have a different song then the other models.
TotallyNotNess Oct 17, 2024 8:38 PM
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MEGA
Mizuki545 May 5, 2024 3:59 PM
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@LammyfromUJL
also sonic in cd model 2 (in the head):
also bizzare
esponjaresource Sep 22, 2023 8:36 PM
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most of the stuff: calm.
the first eu model:
BIZZARE
LammyfromUJL Sep 16, 2023 2:20 AM
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@LammyfromUJL That might be difficult to rip, due to the cycling palettes.
I-like-Sonic-91 Aug 16, 2023 6:35 PM
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where is the wondermega and x-eye sprites?
LammyfromUJL Aug 14, 2023 3:31 AM
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Where are is the selection screen when you don't have a game inside?
Stickfin May 14, 2023 1:22 AM
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For some reason, I actually prefer the EU and JPN bios music and appearance over both of the US ones.
SonicStorm478 Apr 12, 2019 8:45 AM
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Im on drugs, right?
Deleted User Dec 16, 2017 5:57 AM
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@Sonicfan32: If so, please have it use the raw colors. :|
Void-the-Bat Nov 18, 2017 10:47 PM
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@Random Talking Bush: I'll make better versions.
Sonicfan32 Jun 21, 2017 11:58 AM
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@Sonicfan32: They were stretched / anti-aliased and therefore unusable.
Random Talking Bush Administrators Jun 20, 2017 3:45 PM
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