How can I tell if a machine has PAE?

Question

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?

score 26 · Accepted Answer · answered Apr 30 '12 at 09:21

26

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.

answered Apr 30 '12 at 09:21

Lekensteyn

But what if you want to know if your computer is PAE capable, but doesn't show the PAE flag? I understand that many Pentium M and Celeron M processors are like that. My old Thinkpad T40 laptop is like that. Is there a way to tell if the capability is there without checking the flag? – Marnix A. van Ammers May 28 '16 at 23:30
@MarnixA.vanAmmers A quick lookup shows that your Thinkpad T40 has an [Intel Pentium M processor of the Banias family](http://ark.intel.com/products/27577/Intel-Pentium-M-Processor-1_60-GHz-1M-Cache-400-MHz-FSB) which does not report the supported flag even if it is supported according to the [Ubuntu wiki on PAE](https://help.ubuntu.com/community/PAE). You can try adding the `forcepae` boot option as described in the wiki. – Lekensteyn May 29 '16 at 09:21

score 7 · Answer 2 · edited Aug 04 '12 at 07:58

7

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.

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edited Aug 04 '12 at 07:58

Rinzwind

answered Aug 03 '12 at 06:31

RolandiXor

Do you also want an image that does support PAE? :+ – Rinzwind Aug 03 '12 at 07:30
@Rinzwind lol I could add one from my other laptop :P – RolandiXor Aug 04 '12 at 02:40
oh I had one ready @roland >:) – Rinzwind Aug 04 '12 at 07:58
@Rinzwind Core i5! Argh I only have a Core2Duo :( – RolandiXor Aug 04 '12 at 14:08
yeah, got it VERY cheap this notebook (even let an i7 go for it: since I got 50% discount on it for it being displayed in the window of the shop). It's a real delight: 1x120Gb ssd and 1x500Gb hdd. Ubuntu starts up in 7 seconds _O- – Rinzwind Aug 04 '12 at 15:30

score 3 · Answer 3 · edited Jan 19 '14 at 00:35

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.

edited Jan 19 '14 at 00:35

Eric Carvalho

answered Jan 19 '14 at 00:15

linuxdude

score 1 · Answer 4 · edited Mar 12 '19 at 20:47

1

Try:

inxi -f

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

inxi -f | grep -i pae

edited Mar 12 '19 at 20:47

Jeff

answered Mar 12 '19 at 15:15

Talevis

4 Answers4