In some mail I received from Ted Lemon, sie wrote
> 
> 
> > Add UltraSparc to that list too.
> 
> What, of processors for which it's too bad I can't get a standardized
> PCI ATX motherboard?   :')

No.  You can get ATX PCI motherboards from Sun which are designed for
Ultrasparc processors.

http://www.sun.com/sparc/SPARCengineUltraAX/