Motherboard cluster!

[3dmodeler]

hi there, i have recently been looking at the new tyan 16 core work station! however with a price tag like what they have on it, it is out of the question! does anyone know anything about linking motherboard's to achieve more cores/ higher speeds? as need a faster pc for rendering! obviously i will need some form of cluster software witch can be quite costly "to purchase"! but can this be done with standard mobo,s and amd dual core cpu's or will i need server boards and cpu's, in advance thank you to anyone who can help me with this!