Most of the sound card never really advertise the number of voices they can do (not talking about mono sound surround sound.Just polyphony).Will the newer games support the ammount the card can handle or they just use mixing multiple channels in software.
No, the number of hardware voices supported is a through back to the old EAX era.
With newer software/games, processing is done on the CPU, mainly using the sound card as a DAC or ADC.
With CPU processing, you can specify any number of voices required and get the same results on any sound card (at least until you convert to analogue).
The number of voices supported in hardware processing is irreverent to newer software/games.