tikz example

backpanel.tex

\documentclass{standalone}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}

% outside border
\draw[step=1cm,gray,very thin] (-1.9,-1.9) rectangle (31.9,6.9);

% back panel frame
\draw (0,0) rectangle(30,5);

% power
\draw (2,2) -- (5,2) -- (4,3) -- (3,3) -- cycle;

% ps2
\draw (6,2) circle(12pt);

% ps2
\draw (6,3) circle(12pt);

% usb1
\draw (7,1) rectangle(9,1.5);

% usb2
\draw (7,1.75) rectangle(9,2.25);

% ilo
\draw (7,3) rectangle(8,4);
\draw (7,3.75) rectangle(7.25, 4);
\draw (8,3.75) rectangle(7.75, 4);

% db9
\draw (10,1) rectangle(12,2);

% db15
\draw (13,1) rectangle(15,2);

% net1
\draw (16,1) rectangle(17,2);
\draw (16,1.75) rectangle(16.25, 2);
\draw (17,1.75) rectangle(16.75, 2);

% net2
\draw (18,1) rectangle(19,2);
\draw (18,1.75) rectangle(18.25, 2);
\draw (19,1.75) rectangle(18.75, 2);

% dag timesync
\draw (23,3) rectangle(24,4);
\draw (23,3.75) rectangle(23.25, 4);
\draw (24,3.75) rectangle(23.75, 4);

% dag ports
\draw (24,3) rectangle(25,4);
\draw (25,3) rectangle(26,4);
\draw (26,3) rectangle(27,4);
\draw (27,3) rectangle(28,4);

\end{tikzpicture}
\end{document}