Please retry without acpi=off and if that fails, use the boot option splash=none to be able to scroll back (with Shift-PageUp) and read the kernel messages.
How does the machine freeze? Does it still respond to CapsLock? How long did you wait? Do any of the keyboard lights blink during the freeze? Can you hit Ctrl-Alt-Del?
removing acpi=off didn't change anything, freezes on same point. The machine freezes after the said last message, cursor is blinking on the next line for a few seconds, then stops blinking. No keyboard lights blink during freeze. After this the keyboard doesn't respond at all, no reaction on CapsLock or Ctrl-Alt-Del, so I also wasn't able to scroll back to read all the kernel messages. I once left it in "frozen state" for approx. 2 hours, having a cup of coffre then. Usually I don't wait at all. I just try do hit something on the keyboard and then push the reset button of the PC...