Enlarged substrate for magnetic recording medium

An apparatus comprising:

• a magnetic recording disc comprising a substrate and at least one magnetic recording layer supported by the substrate;
• a motor adapted to rotate the magnetic recording disc about a central axis;
• and
• a housing member having a base portion adapted to support the motor so that the magnetic recording disc rotates in a clearing relation to the base portion, the housing member further comprising a sidewall which extends in a direction substantially normal to the base portion adjacent an outermost circumferential edge of the magnetic recording disc, the substrate characterized as an enlarged substrate, the enlarged substrate having an overall diameter of at least 96.9 mm responsive to the housing member characterized as a base plate for a 3½ inch form factor HDD and the enlarged substrate having an overall diameter of at least 66.9 mm responsive to the housing member characterized as a base plate for a 2½ inch form factor HDD.