<BR>
'''RECOMMENDED''' to do so, if you're either using:<BR>
* [[464Plus_Conversion#Jonathanen.27s_Easy_Way_To_464.2B_Conversion|Upgraded CPC 464+ to 6128+ spec ]] <BR>
* Unexpanded CPC 464 without CPC 6128 OS/BASIC ROM installed with both DDI-1 3" & 3.5" external disc drives connected only.
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