For UK/EU and US Dreamcast, on the bottom of your Dreamcast, look for a number in a circle near the word PAL or NTSC or NTSC U. If the number is 0 or 1 then it will work as the followings. For Japanese Dreamcast, on the bottom of your Dreamcast, if the HKT number is HKT-3000 and the model number is NOT 670-14071G, then it will work as the following.
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