The ornamental design for an all-in-one computer, as shown and described.
FIG. 1 is a top front perspective view of an all-in-one computer showing our new design;
FIG. 2 is a front view thereof;
FIG. 3 is a rear view thereof;
FIG. 4 is a left side view thereof;
FIG. 5 is a right side view thereof;
FIG. 6 is a top view thereof;
FIG. 7 is a bottom view thereof;
FIG. 8 is a top rear perspective view thereof; and,
FIG. 9 is another rear view thereof, showing a more clearly visible speaker portion.
The broken lines illustrating portions of the all-in-one computer are for environmental purposes only and form no part of the claimed design. In addition, the long-dash-short-dash lines appearing in FIG. 9 represent a boundary along which a portion of a stand of the all-in-one computer is removed.