The guys over at Assemblergames and Emuxtras have figured out a way to run Chihiro arcade games on modchipped/softmodded Xboxes with the extra 128mb mod, sadly the standard xboxes only came with 64mb ram so these games do boot on those but they seem to crash after entering the menu (this is the case with Virtua Cop 3 at least.) The cool thing is that the chihiro is very similar to the xbox1 so Virtua Cop 3 even works with the xbox lightgun!.

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The Sega Chihiro system is a Sega arcade system board based on the architecture of the Xbox. The 733 MHz Intel Pentium III CPU and the Nvidia XChip graphics processor are common to both. Unlike the Xbox, Chihiro can support up to 512MB RAM through add-in memory modules. Chihiro games are distributed on Sega GD-ROM media, instead of standard DVD-ROM used by the Xbox.

Because the Chihiro and Xbox share the same hardware architecture, porting from the Chihiro is theoretically easier than porting from a different arcade platform. In practice, the much smaller memory-capacity of the Xbox (64MB), presents a formidable challenge for home-conversions of arcade titles which use Chihiro's larger memory configuration, however the Xbox release of OutRun 2 was able to retain the look and feel of the original 512 MB arcade version."

Games available for Chihiro:
Crazy Taxi High Roller
Ghost Squad
Gundam Battle Operating Simulator
Ollie King
Out Run 2
Sega Club Golf 2006 Next Tours
Sega Network Taisen Mahjong MJ 2
Sega Network Taisen Mahjong MJ 3
The House of the Dead III
Virtua Cop 3
Ford Racing Full Blown
Wangan Midnight Maximum Tune
Wangan Midnight Maximum Tune 2