Yes you can max out everything, that means have 4 PATA and 2 SATA.
I havent heard of anyone putting 2 PATAs to a SATA controller through a convertor and a single SATA port. I do know that the digital protocol layer allows master/slave stuff, for backwards compatibility, but I dont know if this allows you to actaully have 2 devices.
IMO I think it was SUPER SUPER DUMB that they didn't allow for daisy chaining on SATA. And with the upcoming 300mbs SATA, yeah, what in hell do you have that can make 300mbs when you can only have 1 device on that channel? If you have multiple devices working at the same time you can saturate that,
but I DARE ALLL of OC forums to find me a device that can sustained use (cache transfers dont count) of that bandwidth (300mbs) and that ISN'T a solid state drive.