I'm attempting to install Slackware (14.1 64bit) onto a 16GB SD card and have it boot from the SD card itself. I've downloaded the Slackware ISO, burned it to a DVD and have used it to install to the SD card, which seems to install fine, albeit a bit slowly.

However, when it gets to the point of installing lilo, installing to the MBR fails (I currently do not have a hard drive in the computer), so I'm left having to install to the Root partition. However, upon rebooting, my system tells me that there is no bootable media available.
(I've gone into the BIOS and changed the boot order to look for removable disks first, CD/DVD second, and a hard disk third; I suppose it's possible the BIOS doesn't consider a SD card as a "removable disk" and only looks for USB drives instead, but for now I'm under the assumption that it will look at any card attached to the onboard card reader.)

The SD card has 1 partition and is formatted with ext4, and that partition was marked as bootable with fdisk prior to the installation (and double-checked post-install).

I recently setup Raspbian for a Raspberry Pi and am looking for a similar setup here with Slackware for a lightweight x86 machine. I seem to recall the Pi's SD card having a small FAT32 partition at the front of the card, is this perhaps a requirement to make the card bootable?

I've been Googling for a day or two for a solution but I don't seem to be finding any solid leads. Can someone please steer me in the right direction?

Thanks!

Mine boots fine. A SD card in usb card reader plugged to a usb port. But the card reader integrated into laptop doesn't boots.

If everything else fails, try to make an USB boot stick typing "makebootstick" as root (this should have been proposed in the CONFIGURE step of the installation).

If doing that after installation (hence with a different / ), I would make a backup of /sbin/makebootdisk then hard code in it ROOT_DEVICE as /dev/mmcblk0p1 (that's my guess, check with lsblk) to avoid having to type that at each startup, before running that script.

Then, insert the SD card and the USB boot stick and switch on the machine.

I never actually tried myself, so please tell us if that works

Don't mix arm and x86/amd install or boot methods to start.

A SD card or usb flash ought to be considered a real internal hard drive for most new systems. Boot system with sd card in and go to bios. See that the sd now shows up as a hard drive selection. You move your hard drive boot order up. (better still, remove internal)