the installation should have asked you whether you want dma turned on, if you said "yes" and it was still slow then the chipset is probably not supported. with dma on the installation copies all files in less than 5 minutes on reasonable hardware.
Back when I have been installing it didn't ask anything about DMA. I'll check if I can spare the bandwith to download newest ISO...
when you get to it, run 'pci' and send it to the list. it may turn out that we just need to add the did/vid pair to sdata.c...
I don't know about Xen support (it seems that nobody touched it since wiki article), but my chipset (on both machines) is i440bx - rather supported IIRC :) -- Paul Lasek
