\documentclass{article}
\usepackage{pgfplots}
\pgfplotsset{compat=1.5}

\begin{document}
\begin{tikzpicture}
\begin{axis}[
%axis equal=true, 
scale mode=scale uniformly,
%axis lines=none, 
view={45}{35.26}]
\addplot3 [mark=cube, mark size=2cm] coordinates {(0,0,0)};
\end{axis}
\end{tikzpicture}
\end{document}
