Disklavier

I've recently connected an old computer to my MarkIV via an old soundblaster sound card and the MIDI/Joystick cable.

Turns out that that computer probably won't handle what I'd like to do ultimately, so I'm buying/building a new one.  Do I really need MIDI capability on this new computer, or can I just connect the computer to the disklavier via USB?  I noticed that the Disklavier allows you to tell it that MIDI will be arriving via USB, so I suspect that this is possible.  Will I need to install drivers for this on the computer?  Where can I get those?

Thanks in advance.
-Kevin