Actually HDMI 1.4 is the ONLY specification that supports 3D, DVI does NOT. If that is what you want then you'll need an ATI card that supports HDMI 1.4 specification.
So even if your hardware supports the ability to output a 3D signal (most newer video cards are more than powerful enough), the DVI specification doesn't support the #D signal. A 3D signal requires A LOT more data bandwidth than the DVI (physical) cable specification can handle.
Also, you really want HDMI 1.4b specification and this will support 3D at 120 Hz. And finally, HDMI 2.0 specification should be coming out this year.
But DisplayPort is actually a better connection (supports more bandwidth).
ATI 5000 series cards only support HDMI 1.3 specification and I don't think the HDMI 1.4 specification was even available at the time the 5000 series cards were being developed.
So Microsoft and AMD aren't really hiding anything. I know you probably don't want to hear that but no driver update is ever going to make a 5770 work with 3D and HDMI 1.4 specification.
-------------------------
"For me, it is far better to grasp the Universe as it really is than to persist in delusion, however satisfying and reassuring." - Carl Sagan