Ok! at last I solved it
Thanks milanca for your time, It was easy once you told me how to resolve the issue with OSx86 tools, After installing the base system I started OSx86 tools, from there I went to Add efi string/boot flag, I choose my Gfx card i-e 8500 GT 1GB generated the string and applied to apple.boot.plist. Reboot..... voila... its done