Using Multiple Graphics Cards with OpenGL

hi all,
iam using opengl-0.3 and two nvidia quadro fx5800 graphics for running my application. inorder to use multiple graphics cards with opengl,
1.which version of opengl libraries shall support multiple graphics with opengl feature.
2.whether this x11 functions are applicable for windows environment as iam using msvc.
3.how to get card id from the XOpenDisplay() function.

Thanks,
Bhanu S

PLEASE continue here :
http://www.opengl.org/discussion_boards/ubbthreads.php?ubb=showflat&Number=275440#Post275440
No need to crosspost.