What is the ultimate fastest platform for php? Is it nginx+freebsd?

I was wondering what is better for a php server. I heard that nginx is
the fastest server and freebsd is fastest unix os.
Would freebsd 64bit + nginx be the best choice? Some even say iis 7.5 on
winserver 2008 r2 is the fastest for php, but I think they’re kind of
biased with the ease of windows (or think like - this is serious
product, must be better than free stuff).

Posted at Nginx Forum:
http://forum.nginx.org/read.php?2,175274,175274#msg-175274

Personally I prefer debian + nginx + php5-fpm, freebsd does perform
better
with nginx apparently thuoug an its definately not windows for
performance,
anyone who says that is misguided.