This is really bug somewhere, maybe in initramfs or syslinux - Ubuntu 12.04 doesn't start from CD/USB with error message about missing PAE feature in CPU, but works fine with the same CPU and same kernel after installation. Also it seems Ubuntu 12.04 starts fine when the same installation disk is started from GRUB boot loaded, for example when WUBI is used!
I can confirm that oliver (oliver-schinagl) is telling true - yesterday I tried to start Ubuntu 12.04 CD on Fujitsu laptop with Pentium(R) M processor 1.60GHz (model: 13, stepping: 6, cache: 2MB) and got error message "following features not present on the CPU: pae. Unable to boot ..." But the same kernel works fine with the same CPU after installation - it's very easy to check this: 1. I attached hard disk from this laptop with Pentium-M 1.6GHz CPU to another computer with newer CPU and installed Ubuntu 12.04 with PAE kernel in laptop's hard disk. 2. Then I put hard disk back to my laptop with Pentium-M 1.6GHz CPU (without PAE flag, see attached /proc/cpuinfo file) and Ubuntu 12.04 with PAE kernel works fine on laptop, where LiveCD refuses to start! I even installed all updates, including newer PAE kernel and still working without any bugs! Unity 2D works fine on this computer, Gnome Classic works fine too, I'm using computer for 2 days without any problems, so, PAE kernel works fine and bug exists only on LiveCD/LiveUSB. Maybe somewhere LiveCD checks for CPU flags and stops to boot if pae flag is missing? Ubuntu developers, please reopen this bug and fix it - this is an important *regression* for lots of people. If you need any info just tell us, I know several computers where Ubuntu 12.04 doesn't boot from CD because of PAE error, but the same PAE kernel works fine after installation... I'm attaching /proc/cpuinfo file and uname -a output on the same computer is: ubuntu@ubuntu:~$ uname -a Linux ubuntu 3.2.0-24-generic-pae #39-Ubuntu SMP Mon May 21 18:54:21 UTC 2012 i686 i686 i386 GNU/Linux ** Attachment added: "/proc/cpuinfo-Pentium-M-1.6Ghz-2MB-cache-no-PAE" https://bugs.launchpad.net/ubuntu/+source/linux/+bug/930447/+attachment/3176020/+files/cpuinfo-pentium-M-1.6-2MB-cache-no-pae.txt -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/930447 Title: Unable to Install Ubuntu 12.04 on Pentium M x86 Laptop due to bug in PAE kernel, initramfs or syslinux To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/930447/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
