2.6.2. Plymouth
Plymouth is the graphical boot up system debuting with Fedora 10.
Adding rhgb on the grub command line directs Plymouth to load the appropriate plugin for your hardware.
The graphical boot splash screen that comes with Plymouth requires kernel mode setting drivers to work best. There are not kernel modesetting drivers available for all hardware yet. To see the graphical splash before the drivers are generally available, add vga=0x318 to the kernel grub command line. This uses vesafb, which does not necessarily give the native resolution for a flat panel, and may cause flickering or other weird interactions with X. Without kernel modesetting drivers or vga=0x318, Plymouth uses a text-based plugin that is plain but functional.
Currently, only Radeon R500 and higher users get kernel modesetting by default. There is work in progress to provide modesetting for R100 and R200. Additionally, Intel kernel modesetting drivers are in development, but not turned on by default.
The kernel modesetting drivers are still in development and buggy. If you end up with nothing but a black screen during boot up, or a screen with nothing but random noise on it, then adding nomodeset to the kernel boot prompt in grub disables modesetting.
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Plymouth hides boot messages. To view boot messages, press the Esc key during boot, or view them in /var/log/boot.log after boot up. Alternatively, remove rhgb from the kernel command line and plymouth displays all boot messages. There is also a status icon on the login screen to view boot warnings.