It would help to know what the error was. If it tells you to use noapc, and you have, then that's not the solution to your problem.
Since Linux XP is commercial software, you should probably also ask at the company's support page.
http://www.linux-xp.com/support/
It should be telling you to type something like pci=noapci (although this may depend on the kernel version). You can find out far more about command-line parameters than you ever wanted to know at
http://www.kernel.org/pub/linux/kern...n_pdf/ch09.pdf