That is a bug in Fedora 17. What happens is grub2 tries to set your resolution to a mode that isn't supported by the video adapter.
Anything over 1280x1024 isn't in the vesa specs so may or may not be supported, but it appears that grub sees what the monitor can display and tries to set that mode, even if the video adapter can't display it in vesa mode.
If you let it sit there, it will boot normally, you just can't see anything on the screen until it loads your video drivers.
Once it boots, you can edit your /etc/default/grub file and force a mode it can display.
Just add these lines to your /etc/default/grub file:
Then rebuild your grub.cfg file
grub2-mkconfig -o /boot/grub2/grub.cfg
All of this has to be done as root user