Kernel panic without "pci=nosort text" at boot

Hi:
With almost every Linux distributions I've tried (Fedora 3 & 4, Suse
9.3 and a Portuguese version of Linux "Caixa Magica") if I don't have the
option "pci=nosort text" at boot I get a "Kernel Panic: not syncing,
attempted to kill init" and a system freeze. With Suse 9.3, which I have
installed on my system, this option is already included in the boot
sequence, so there is no need to put it by hand. However, if I choose the
safe mode, I get a system freeze if I don't write it at boot.
Does anyone knows why this happens? Is it a kernel bug, or hardware
incompatibility?
My guess is that it has to do with the video card, which in my case is ATI
Radeon X600 PCIE. Is this true?
Regards.
Joao