Seems to be a bios function.
Here is my experience with netbooks...
Most conservative approach is to edit the existing grub menu.lst to add tinycore
Make and copy tinycore files and extensions to these directories.
Boot and test. Then delete Xandros directories, be sure to leave boot/grub
Multi device boot will of course still work, as only directories and grub menu were touched.
I have done this to an eeepc 900A 4MB SSD and to a Dell Mini 9 4MB SSD
If you use the automatic installation script in tinycore, usbinstall, it will wipe out the grub boot loader.
On an eeepc S101, I used the usbinstall script, ext option to wipe out an XP installed on 16MB SSD.
It boots fine with extlinux boot loader and the auto installation worked great.
It still has the multi device boot available.