not present: cmov - AMD

[Glkanter]

I tried to run Ubuntu 11.10 from the cd on an old Compaq Presario 1200 with an AMD chip. The boot failed immediately with:

This kernel requires the following features not present on the CPU:
cmov
Unable to boot - please use a kernel appropriate for your CPU.

I remember reading about this anomaly from a previous experience.

Are there any other 'flavors' of Ubuntu that will run on this chip?

Thanks!

[Glkanter]

Lubuntu 11.10 has the same problem.

[matt_symes]

Hi

cmov is an assembler instruction that was introduced with the Pentium pro processor. Your PC does not have it. It is an optimised move instruction.

You need a distribution that has an old kernel. Ubuntu will not work with that current kernel.

You can

1. try a different distribution such as puppy linux. (You need a i486 or i586 architecture if i remember correctly) (a 2.4 kernel variant will work i think).
2. Try to find a kernel that will work with Ubuntu (not sure if that is possible)
3. Compile your own kernel without the cmov instruction.

You will need to do some research.

Kind regards

[Glkanter]

Xubuntu gives the same message.

[Glkanter]

Thank for the response.

I'll search for 'puppy linux.'
I find #2 confusing.
#3 is out of the question for me.

Thanks!

[matt_symes]

Hi

From here

http://bkhome.org/blog/?viewDetailed=02418

Lucid from Ubuntu is compiled such that it will run on 486 computers. Maverick and up needs a 686 coputer. The main reason for the change was to take advantage of the cmov instruction, Lucid will install and run on processors that do not have the cmov instruction. I use it when repurposing old thin client boxes based on the the VIA c3 or C7 or the geode(all without cmov support).

Maybe try Lucid (Ubuntu 10.04). That is going to be supported until April 2013.

Kind regards

[Glkanter]

Thanks for the suggestions. I'm downloading Puppy and Lucid.

Wish me luck!

[matt_symes]

Hi

Thanks for the suggestions. I'm downloading Puppy and Lucid.

Wish me luck!

Good luck.

Please post back to say how it went.

Kind regards

[Glkanter]

Lucid Alternate (ubuntu-10.04.3-alternate-i386.iso) began the process, then failed with:

Killed
[  140.101932] Kernel Panic - not synching: Out of memory and no killable processes...
[  140.101950]

On to Puppy!

[georgemc]

The assembler instruction "cmov" was introduced somewhere around the 686 introduction, not sure when exactly.

Even though the 32bit Ubuntu ISO download files have a "i386" in their name they are not I386 but I686+ compilations. This I think just adds to the confusion.

You can compile or cross-compile a kernel that does not use this instruction and install it on an older system. It does require some effort, resources, and time on your part.

However: its not just the kernel that can be compiled requiring the "cmov" instruction, the applications can be compiled that way too.

I tried "Puppy" on an old (really old) laptop and was able to boot and install it.

Cheers

George