[arch-ports] New in ArchPPC and some problem

Hi all, I'm new here. I installed Arch in my macmini (G4) using your wiki (great guide), but I'm having some problem to proceed in arch. I'm trying to install X, so I installed: Xorg (and dependencies), xf86-video-ati, xf86-input-keyboard, xf86-input-mouse. I configured X with xorgconfig (I think correctly) but when I try "startx" I've black screen, and monitor does like there is no signal (appears a popup who search for digital or analogic signal). I modified monitor vertical sync like in monitor manual but nothing, X doesn't start. It's not possible to use hwd on ppc to configure it? I think that this is a great project (and arch is a great distro), thanks for your work.