

OK, I found it ... and it is very simple !

1) Login using for example a live CD/DVD or Linux from another partition, etc...
2) Access and edit file ==> /boot/grub2/grub.cfg
3) Find the Stanza booting Fedora, and just add
xdriver=vesa as noted below
(in red).
4) Then you can boot normally in Vesa mode, which will allow you to install the Nvidia Driver
Search the net for something like "Fedora 17 Postinstall"
Andre
=============== THE GRUG.CFG Stanza for Ferora =============
echo 'Loading Fedora (3.4.5-2.fc17.x86_64)'
linux /vmlinuz-3.4.5-2.fc17.x86_64 root=UUID=4e101b4a-b264-4ea6-a8e6-cf148b50a3a5 ro rd.md=0 rd.lvm=0 rd.dm=0 SYSFONT=True KEYTABLE=us rd.luks=0 LANG=en_US.UTF-8 rhgb quiet
xdriver=vesa nouveau.modeset=0 rd.driver.blacklist=nouveau
echo 'Loading initial ramdisk ... xdriver=vesa'
initrd /initramfs-3.4.5-2.fc17.x86_64.img