eeePC 701 error: “This kernel requires an x86-64 CPU, but only detected an i686 CPU.”

I keep coming across this issue on my eeePC. I’ve solved it more than once, but I never make note of how I solve it.

The issue arises when I botch an OS install. The lastest iteration of this error was caused by a failed ubuntu mini image installation via PXE. Halfway through the installer, I encountered an error (I didn’t make note of this either!) and I hard reset the computer. Trying again, I get this error. Notice the directory we’re trying to boot to, it’s i386 which is what our eee needs.

*fumbling about for hours*

The issue seems to be not the laptop, but the data the laptop is trying to boot. What are we trying to boot? Files copied from a CD (actually an iso that I mounted to a loopback device, but whatevs). Somehow we seem to have corrupted these files we are booting to, I’m thinking I didn’t mount these files as read-only. To solve the issue, I got rid of the middleman– the files I copied from the CD then mounted. I deleted these corrupted files, mounted the original iso to a loopback device, and allowed the PXE tftp to read directly from the loopback device (mounted as read-only.)