How can I tell if a machine has PAE?

I want to help someone upgrade an oldish laptop from 11.10 to 12.04, which requires PAE. I am not sure whether they have PAE or not.

I know it is likely that they do have it after all, but how can I tell before trying to upgrade?

Solution 1:

Citing https://help.ubuntu.com/community/EnablingPAE:

To check if your processor supports PAE, try

grep --color=always -i PAE /proc/cpuinfo

If it outputs something, you have PAE support. Otherwise, the output will be empty.

Solution 2:

Another option (which uses a GUI) involves using Hardinfo (System Profiler and Benchmark.

• Under devices, select Processor.
• From here, you can see the processor's capabilities (along with their simple descriptions).
• If PAE is not listed, your processor does not support it.

• As you can tell, the processor in this example does not.

• and this one does.

Solution 3:

From the terminal, simply type the following.

cat /proc/cpuinfo

Scroll down and check the flags. PAE will be listed in the flags if supported.

Solution 4:

Try:

inxi -f

Or, to see it in red color (if present):

inxi -f | grep -i pae