i have installed successfully my iATKOS v5i (Leopard 10.5.5) yesterday. I have even use it for a while

i use dualboot method for XP (copied the chain0 and edit boot.ini) and have successfully boot Mac OS yesterday..

but today when i try to boot mac, nothing happens... i just saw underline blinking. but nothing happens...it supposed to showing darwin bla bla bla.....and option for startup
the boot0=mbr and boot0=done have successfully done

can anyone help me what the problem this is???
Thx before...

same problem help please