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I installed FC 15 onto a laptop that previously had XP installed. While XP reported that Physical Address Extension was enabled, I am unable to find any reference to it in Fedora. How can I tell if the kernel I'm running supports it, and how can I enable PAE if it's not currently supported?

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up vote 2 down vote accepted

Type uname -a or cat /proc/version and see what the kernel string looks like - for example:

Linux aa1.localdomain #1 SMP Wed Jul 6 14:29:06 UTC 2011 i686 i686 i386 GNU/Linux

If 'pae' (or 'PAE') isn't there then your kernel doesn't support PAE

If you do not have the PAE kernel installed, issue the following command (as root):

yum install kernel-PAE

Then reboot

Just to make sure your processor supports PAE, you should do the following first:

cat /proc/cpuinfo | grep -i PAE

If there's no sign of pae (or 'PAE') in the output, your processor doesn't support that mode.

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Try using grep address /proc/cpuinfo, and the output should tell you if PAE is supported.

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What should he look for? Could you provide a sample output? – Simon Sheehan Aug 31 '11 at 14:31

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