You wouldn't get anywere close to Window's theoretical maximum.
You'd run into huge performance, hardware, and reliability issues well before that happens. RAID is simply not a viable choice when handling absolutely monolythic amounts of information.
I am guessing you would be able to run a few terrabytes worth of information, depending heaviliy on the hardware, before you would start hating yourself.
Not that I've ever had that much information to deal with, but that is my understanding of it.