I've used Universal USB Installer to create a bootable USB drive to install ubuntu 12.10 desktop edition. The flash drive was booted correctly, but a black screen with a lot of messages was displayed here is the last line :
[ 506336] [drm] driver supports precise vblank timestamp query
I think that the problem is from the graphical card. There are some lines before the above one that display information about Radeon which is my graphic card type.