I want to put UNIX BSD on it
but I can't access the BIOS and I can't boot from the CD drive.
I've tried everything I know.
The current OS is a Win98.
From what I've read, the Compaq Armada 1560m is a laptop:
Processor: Pentium MMX @ 166Mhz, 66Mhz FSB
RAM: 16MB installed, 80MB Max (EDO RAM)
HD: 2.1GB
Video: 800x600 Passive Matrix, 2MB VRAM.
OS Windows 95 With Internet Explorer 4 (is what it came with)
It doesn't possess any network capabilities as is, so Transfusions suggestion is out. Regardless of what BSD variant you choose, I doubt you'll be able to run any desktop environment, so you'll be left with the shell, probably. Can't hurt to try X.org, I guess, but don't be too hopeful...
FreeBSD system requirements can be found
here.
You would likely need the FreeBSD/pc98 distribution.
-if the system still has the stock 16MB, it won't meet the requirements of 24MB of RAM.
The only interface it seems to have that you can work with to install it is the floppy drive. Also, the way to get into the BIOS is typically F10 or F2 during startup. But, you need to have installed a piece of firmware called "ROMPAQ" or something in order to make changes to it. I cannot find any links to that software anywhere, myself.
As for installing FreeBSD using floppies, be sure to set aside an afternoon. here is the
FAQ. From what I gather, you have to download the "full" FreeBSD, and then it contains floppy images which you then transfer to floppies, and use to boot the system to which you are installing FreeBSD. I'm not sure what the procedure entails after that, if I had to guess I'd say it would be able to pull the rest of the data from the CD-ROM for installation (assuming the download is in fact a CD-ROM, that is).
Good luck.