glPerspective

I draw cube on the screen and it was visible while i had …

glOrtho(-5000.0, 5000.0, -5000.0, 5000.0, -5000.0, 5000.0);

Now I blocked ortho and want to play with glPerspective and I called it like this…

gluPerspective(100.0, 800.0 / 700.0,100,5000);

where 800 and 700 is my window size.I cant get anything on the screen no matter how i modify numbers in the glPerspective. This is all I get… (attachment)
Can anyone point me somewhere to get my lovely cube back on the screen with glPerspective.

Thank you

What are the z-values for the vertices of your cube? Understand that the z-values of your cube must lie within -100 and -5000 for them to be visible with gluPerspective.

More information about these functions can be found here
http://www.opengl.org/sdk/docs/man/xhtml/gluPerspective.xml
http://www.opengl.org/sdk/docs/man/xhtml/glOrtho.xml