These iPXE scripts can be used on OVH Dedicated Server with the iPXE Customer Script feature
#!ipxe
set base http://fedora.mirrors.ovh.net/linux/releases/21/Server/x86_64/os
kernel ${base}/images/pxeboot/vmlinuz repo=${base} inst.vnc inst.vncpassword=YOURNONSECUREPASSWD ifname=eth0:${netX/mac} ip=eth0:dhcp nameserver=213.186.33.99
initrd ${base}/images/pxeboot/initrd.img
boot
#!ipxe
set base http://mirror.ovh.net/ftp.centos.org/7/os/x86_64
kernel ${base}/images/pxeboot/vmlinuz repo=${base} inst.vnc inst.vncpassword=YOURNONSECUREPASSWD ifname=eth0:${netX/mac} ip=eth0:dhcp nameserver=213.186.33.99
initrd ${base}/images/pxeboot/initrd.img
boot