I guess you've given up on 2 IDE connector boards, but ... oh, well.
I'm holding on to see what a motherboard based on the Nvidia 650i Ultra chipset might look like. Though I'm sure they will also only have 1 PATA connector, technically the 650i chipset supports 4 PATA devices. In reality, any new motherboard will probably continue the "We hate PATA" trend.
Another possible option is a PATA to SATA converter dongle like
this one. Do they work? Sometimes. For some people. Would it work for you? I have not the faintest idea. Ya pays ya's money and ya takes ya's chance.
I've got one of these dongles and I've got a spare 120GB PATA drive. So I guess I really should take a few hours sometime and see if I could get Windows XP to install and boot on my IDE drive via a SATA port using it. However since I have a Pentium 3 system, whatever the result it wouldn't be applicable to anyone else , but still ... I wonder if it would work.
-john, the redundant legacy PATA dinosaur