If you have a freeze problem during startup and the splash bar is not proceeding, edit the grub screen by pressing the “e” button on the keyboard and remove the “splash” and “quiet” parts from the kernel parameters to see what is going on during the kernel boot process. At my situation the problem was related with r8169 module. I had installed Ubuntu Hardy 64bit desktop edition to my laptop. When i checked the messages i realised that just after r8169 loading, boot proces was freezing. So by playing kernel parameters like adding pci=noacpi pci=nopci, somehow i managed to reach the desktop and blacklist the r8169 by adding the line “blacklist r8169”. Then recreated the initramfs by update-initramfs -u. At the next reboot the problem was removed.