Dual-boot with two diskdrives
 

I have set up a friend's computer with Linux on an extra disk in addition to Windows XP. This is so he can try it out before deciding whether to commit to changing. On my spare computer this works, I just have to press a key when booting to select which hard drive to boot from. On his there is an option to press F9 for boot options but all that shows is a selection between device types (CD, HDD, USB) no choice of which drive. I have made them master and slave on one PATA cable, then tried master and master one on each PATA cable, but neither works. The limitation appears to me to be built-in to the BIOS. Am I right?

It's an HP Compaq d330DT.

Those older computers, especially if they are pre-built ones, like from HP or Dell, often lack such options. You have several options to circumvent that:
- add the Linux installation to the Windows bootmenu: https://bkpavan.wordpress.com/2008/0...bootloader-xp/
- Install a Linux bootloader, like Lilo or Grub
- Use a bootloader-CD, like SuperGrubDisk, to boot the Linux installation.

Since this is only for testing I would recommend to use the third approach.

I have an older machine here that behaves the same way. It's a BIOS limitation. TobiSGD had the right suggestion ie via bootloaders. I used the 1st option on my laptop.

Firstly thanks for reading my question carefully!
Thanks for confirming my suspicion.
I agree, I don't want to mess about with his Windows installation. Your third option looks the least intrusive, but although I don't know SuperGrubDisk I expect it would be quite technical, so there is a risk he might do something nasty.

I think he will have to make do with my demo from a live DVD.

Thanks NyteOwl!

You need to change the boot device order. Move one hard drive over the other.

Actually it is quite easy, just boot from the SuperGrubDisk, select the default "Scan for operating systems" option and after that choose the OS you want to start. Not more technical then running an OS from a CD/DVD, but you get the full speed of the installed OS and no problems with filling the RAM when trying to install software (which might easily become a problem with older machines with not so much RAM).

The website made it look dodgier than it is. I've just tried it on my PC and it doesn't look too difficult or dangerous, so I will give it a try on his PC. Useful tip thanks!