black screen after upgrade to 11.10 beta ati 5770

after upgrade to beta I get grub screen as usual, then the ubuntu splash, and then black screen.
If I uninstal fglrx, I get to boot the gui but no unity -- just nautilus.
instalation of fglrx-updates yields a strange square instead of a mouse pointer, with broken image as background.

right now I'm back to fglrx and can boot gui after booting recovery mode and then entering startx unity.

how can i make it boot normally??

I have no idea what to include -- which logs and what output...

help me please! 0_o

UPDATE: after changing the GRUB_CMDLINE_LINUX_DEFAULT value on /etc/default/grub to "nomodeset"" instead of the original "quiet splash" now I get a login screen and after loging in a black screen with a x shaped mouse pointer....

just when I thought it was over...

any useful suggestions would be very much appreciated