I would be afraid that passing computer video through the receiver would hinder gaming performance. I have no evidence that it would but it's just one more bit of processing. That's why I use the S/PDIF Digital optical output.
Good luck! I thought the same thing when I bought a
Sansui 9090DB in the 70s.

The thing was a beast but there will always be a newer better must have feature. It may be more more sophisticated audio processing such as a successor to Audyssey MultiEQ XT32. It may be a new completely incompatible video connector system for super-double-bandwidth-blu-ray-on-steroids. It may be mood measuring telepathic auto-tuning.
The HDMI on that Onkyo is simply Pass-Thru, so there is no processing involved.
Besides, how is the Video connected to the Display? Regular VGA connection?
I would assume that 1080p graphics is the goal, right?
And that ATI card has 2 HDMI outputs?
As far as technologies is concerned, sure there are always some minor "improvements", but the major significant ones are now hard to come by.
Back then, you have Stereo sound, and later Dolby Pro-Logic. Now were already have UNCOMPRESSED master-quality sound. How can you improve on that?
With Video, sure, I mentioned 4K & 8K, but the cheapest 4K consumer system out there is like $200,000.
It is going to be a while before that catches on.
I a lot of "purist" people, like myself, couldn't care less about Audyssey and any kind of Room EQ, Tones, or DSPs. A lot of us will always stick with Pure Direct.
I wish I could custom build my Pre-pro like a PC.
I would not include 80% of what is in there, including Audyssey.
