In this case, if you look here, you can see as plain as can be that NV specifically states you can use SLI in up to 1080i mode on an HDTV.

The problem is that if you look on the forums, here and here, you will see that it doesn't work. NV, in its usual helpful way is quick to ignore the problem, and like all other matters of this nature won't so much as respond to cries for help.
If it is up to its usual form, they will respond to public shaming by deleting the posts and pretending it never happened. If asked, it will do the usual pretending they didn't realise it was a problem. Like the 6800s and video acceleration, there is little if any chance that things will be fixed, be they box art or silicon. ยต