The ornamental design for a toppanel for a computer chassis, as shown and described.
FIG. 1 is a right side elevation view of a top panel for a computer chassis
showing my design features shown in broken lines are for illustrative
purposes only and form no part of the invention;
FIG. 2 is a rear elevation view of a top panel for a computer chassis
showing my design features shown in broken lines are for illustrative
purposes only and form no part of the invention;
FIG. 3 is a top plan view of a top panel for a computer chassis showing my
design features shown in broken lines are for illustrative purposes only
and form no part of the invention; and,
FIG. 4 is a left front isometric view of a top panel for a computer chassis
showing my design features shown in broken lines are for illustrative
purposes only and form no part of the invention.