The ornamental design for a magneticstorageunit for a data processingsystem, as shown and described.
FIG. 1 is a perspective view showing the front, top and right side of a
magnetic storage unit for a data-processing system incorporating my new
design;
FIG. 2 is a rear elevation of the storage unit of FIG. 1.
The left side of the storage unit of FIGS. 1 and 2 is indentical to the
right side as shown in FIG. 1.