Ubuntu thinks all four of the test pc's have "sda". They are all ata drives.
Now the Presario has an ata and a sata. The ata is where tinycore is and it calls it "sda". Ubuntu thinks the sata is "sdb" but I'm not using it with tinycore.
The other three have ata drives, and tinycore calls them "hda". I've run Ubuntu, Debian, Slitaz, Slax, Fedora, Suzi, ... and they all call them "sda". Except tinycore with it's "hda".
Maybe the installation instructions might list trying hda if sda doesn't work....first clue, backup failed, referring to a /temp/backup_status file which did not exist.
Up and running fine, minefield with flash10 video (with a little fiddling) and all,
Jerry