MultiMode3, stand aside! It works nicely on many of the older PlayStation revisions, but Sony (creator of all things PlayStation) added another complication to the little PAL PS one SCPH-102: an additional territory check in the boot ROM.

Enter ONECHIP, the modchip firmware that combines normal disc-authentication behaviour with a boot-ROM patch to bypass that extra check for imports. A conventional modchip that only handles disc authentication doesn’t bypass the additional PAL PS one check by itself. Naturally, now we have to install one.

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