Installing Ubuntu up on my Panasonic Toughbook CF-30 fails. Every time I try to boot to the DVD that I burned the distro image onto, it gives me an error message with something to do with a PAE kernel. (I can't remember the exact error message).
It does have a 64-bit CPU, the Core Duo L2400 running at 1.66GHz. I eventually would like to run Ubuntu alongside the Windows XP that is installed on it, but obviously if it won't boot into the boot menu, thats impossible.
A number of older Pentium M processors produced around 2003-4 (the Banias family) do not display the PAE flag, and hence a normal installation fails. However, these CPUs can run the latest (and PAE-demanding) kernels if only the installation process is modified a little. The problem is not missing PAE, it's about your 64-bit CPU not displaying its full capabilities.
However, the Toughbook model in question has a CPU < 2GHz, and only comes standard with 1/2 GB of RAM; either fails the minimum requirement for Ubuntu 18.04.1 LTS.
I would suggest, instead, Xubuntu or Lubuntu, both of which are less demanding. Xubuntu gets the job done for me.
Multiple sources verify you can replace the 5400RPM HDD with an SSD, which is perceptibly faster. SSD pricing has fallen like a rock recently. Ask anyone who's done it if it was worthwhile.
And, if you have not maxed out the memory in it, please consider doing so.