I Just realized that there are posts on here from users who are running a much newer kernel (3.16) than the 3.8 version I am running.
I am facing problems with intermittent failure to reboot, which I believe may have been fixed in kernel 3.13.
I have just done a fresh install using: http://archlinuxarm.org/os/ArchLinuxARM ... est.tar.gz and that installs 3.8.13-35-ARCH
But there is no attempt to update the kernel when I run pacman -Syu so how do I get the latest kernel that other posters seem to be using ?