What is a PAE kernal and how do I get one? I am attempting to load Ubuntu on a Dell lattitude d600 and get the message:This kernel requires the following features not present on the CPU: pae
unable to boot - please use a kernal appropriate for your CPU.
The CPU is a Pentium M 1.40 GHz/600 MHz.

I think you misunderstand the error message. The kernel you have requires PAE, but your CPU does not support it. this link provides some hints for how to resolve the problem.

Simple, use the 32-bit version, not the 64-bit.

PAE is Physical Address Extension. It allows 32-bit to become 52-bit.

The kernel is telling you your processor cannot do that. Your processor does not physically have 52 bits therefore it does not support this feature.

Alex Brinister

I was going to suggest he mini iso but btmiller beet me to it. I used it to install ubuntu in virtual box & it uses the Debian installer. Using it in expert mode you have a wider range of choices & can enable repos during the install. I also believe it gives you a choice of kernel to install also.

PAE is 32-bit, 64-bit has no need for it. The fact that he's receiving that message means he's already trying to install the 32-bit version of the OS.

I tried the 64 bit version. The result is the followind message:

This kernel requires an x86-64 CPU, but only detected an i686 CPU.
Unable to boot – please use a kernel appropriate for your CPU.

Further input would be greatly appreciated.

You have a 32-bit CPU, which means you can't run a 64-bit kernel. Your CPU also doesn't support PAE, which means you can't run a 32-bit PAE kernel. What you need is a 32-bit non-PAE kernel. I'm not sure if this is possible with the new Ubuntu distros, as I don't use Ubuntu, and I rarely use 32-bit OS's so I'm unfamiliar with which ones do and do not use PAE kernels by default, but I'm 100% sure it will be possible...you just may need to use a different distro.

Ubuntu 12.04 uses a PAE kernel. But you can use the earlier versions like 11.10.

While I've never run into this problem, apparently it's an issue on the later releases. You can still use 12.04 on non-PAE capable hardware, this link will explain it:

http://www.webupd8.org/2012/05/how-t...n-non-pae.html

You didn't mention the ram size or hard disk size of the system. With an obsolete CPU, I expect other aspects of the system might be similarly obsolete. In that case, you might want to ask which Linux distribution is "light weight" enough for your hardware, rather than how to install Ubuntu.

If you really want to press ahead and install a current version of Ubuntu, guyonearth's answer in post #10 looks right. But I expect you don't have enough ram for a current version of Ubuntu to run acceptably (maybe not enough for it to run at all).

The "standard" memory on a Dell latitude d600 was 128MB. The recommended "minimum" memory for Ubuntu 12 is three times that much. In theory, a Dell latitude d600 could be configured with up to 16 times its "standard" memory, so your Dell might have enough ram for Ubuntu (but I still will guess that it doesn't).


PAE is now the default and you have it already, and that is the problem. You need a non PAE kernel.

So you are really unaware how obsolete your CPU is. PAE was supported by x86 CPUs much earlier than 64 bit. A CPU too old for PAE is much too old for 64bit.

Later you posted a much better answer, so it is hard to imagine what you intended by this answer. Hopefully it is not still confusing the OP.

The "52" is seriously wrong. If you had used the correct number (36) the phrasing is still misleading. PAE changes the physical address size from 32 to 36, but in all the many other ways that the CPU is "32 bit" it remains "32 bit". It doesn't become a 36 bit CPU.

But the basic concept of your answer was correct. PAE is a hardware feature required by the kernel the OP tried to use, but not present in the OP's CPU.

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