I somehow added a character to the end of the link, I've corrected the link...

That is still the "online" help file, the revisions to the software since then do have support for audio cards with surround via HDMI, but I really am not even sure if it makes sense to get a new computer for just that functionality.

If you want / need a major upgrade for gaming or HTPC that might make sense, but if you have a desktop that supports older audio cards that seems to yield the same results with REW, of course you'd need to move around audio cables a bit more ...