You guys made me want to use the FW-1884 again!
So I got it back from the storage room and installed an old Firewire card.
I installed it under Windows 8.1 Pro 64-bit with Sonar X3e and it seems to work well.
My only test so far is to open and play back the Sonar X3 Demo - Javier Colon.cwp than came with X3.
It plays back well with 128 samples configured in ASIO.
If you guys have a more complex project for me to try, I'll be grateful to download it.
So my question is: why do you insist on installing a special legacy FireWire driver? Or have I not done something complex enough so far to show the limits of the standard Windows 8.1 driver?