Memory devices having differently configured blocks of memory cells

A memory device has a plurality of individually erasable blocks of memory cells and a controller configured to configure different blocks of the plurality of blocks of memory cells in different configurations, which can include blocks configured to include only groups of user data memory cells for storing user data, blocks configured to include only groups of overhead data memory cells for storing error correction code (ECC) data, and blocks configured to include groups of user data memory cells and groups of overhead data memory cells.