never had an a600 so can't be sure, but maybe it has to do with the boot device priority. normaly floppy has 5, cc0: has 3 and all the other devices must have less than 3. at least in the a1200. from an other point of view it is strange enough for the amiga dos to confuse the boot priorities if the cf card is formated in fat and of course not amiga dos like bootable in any way... (i hope that your are not confused more with this...)
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i have an 1gb kingstone and works fine in any case
