need help understanding the 'no input file specified' issue under fastcgi

[eluser]superfake123[/eluser]
When working on GoDaddy/Dreamhost accounts etc I can set

cgi.fix_pathinfo = 0

and it will fix the issue. However on my own hosting where I have no issues I see that phpinfo() says php is running as fastcgi however cgi.fix_pathinfo is set to 1

So I'm confused. Exactly what are the conditions that causes cgi.fix_pathinfo to be needed set as 0? Is it possible that the phpinfo() check says fastcgi but really php is running as apache module? I honestly am not sure if its apache module or fast cgi, but phpinfo() does say fastcgi.