I did a fresh install of Xubuntu 11.04 on a clean disk. CPU Athlon 64 X2 3600+, 1 GiB of RAM. The machine is about 5 years old and works like a charm normally. Buuut: The normal boot takes about 4 minutes with XU 11.04, including a 3 minute pause time where the machine does nothing (see bootchart 1, kern.log (see lines around 742). If I add "noapic nolapic acpi=off" the boot time is reduced a lot, but there's still a pause of approximately half a minute (see second bootchart image in above link). I also tried disabling legacy USB support in BIOS (didn't change anything).
Especially since there's still a lot of pause in the second boot I'm wondering if there's anything else to help it.
Secondly the first bootchart is making me wonder how the times in there are given. It states the boot process finished after less than a minute which obviously is wrong if you look in the kern.log. Is there something that makes the system like completely frozen in that period of time where it does nothing so bootchart can't even account the time?