Genuine Dell 160w Power Supply PSU for Optiplex GX60, GX240, GX260, GX270, Dimension 4500C and Dimension 4600C SFF Small Form Factor Systems Identical Part Numbers: P2721, 3Y147, 3N200, P0813 7E220 Identical Model Numbers: HP-L161NF3P, PS-5161-7D, PS-5161-1D1, PS-5161-1D1S