Hello again, lots of replies - good!
I am still curious about what kind of work would be required to make a new gfx-card for the amiga, not really considering how commercially realistic it is.
I had completely forgot about the Mediator and Prometheus cards and the Radeon 9200 / Voodoo3 support..
From what I can understand after googling a bit, the final official version of Picasso96 was 2.0, released in 1999, and later versions supporting these newer cards were made by someone other than the original developers. (Matay for Prometheus support, etc.)
So I guess for someone to be able to make working drivers for a new card in 2010, they would also have to modify picasso96 itself in addition to making the driver. (More work, too bad..)
But radeon 9200 and Voodoo3 boards are quite a lot more modern than the old amiga cards, so I guess modern chipsets could be supported as well.
So, on to the hardware side of things..
Todays cellphone GPU's are more capable than the playstation 2. So I imagine the 2D graphics performance required to enable 1920x1080 or similar resolution should be available from cellphone-sized chips. Some graphics memory shouldn't take up a lot of physical space, either. As far as I understand, physical size should not be a problem.
What else than GPU and RAM would a simple graphics card consist of?
By the way, how unrealistic would a 1920x1080 desktop resolution be on an old amiga upgraded with 68030 and a modern RTG card? Will the CPU be a bottleneck, or would it all be dealt with by the graphics card? If it's utterly unrealistic, I would be happy to settle with 1280x720
I can just imagine such a machine, booting up to a nice whdload frontend displayed on the HDTV. With full color and a bit of CPU power, we could even see a modern frontend using the game logos and videos from those crazy people working with the hyperspin frontend. (See hyperspin-fe.com/forum/showthread.php?t=7061)
I understand the chances are slim that there will be another new accellerator board for the a1200 after the ACA1230. But we could always discuss a way to do this in an a500 or cd32
AFAIK, an a500 CPU upgrade usually goes in the 68000 socket, and a graphics card would go in the "almost Zorro2" side expansion slot. With a good flickerfixer on top of denise, we have three different connections! But I imagine hero of the day J.Schoenfelt and his little team could make a magical little board, plugging into the 68000 slot and onto denise, with a small cable running to the expansion slot. (After all, the three are just next to each other, simply begging for it!)
On the cd32 there should be plenty of room, and just one expansion slot required, plus a cable to the flickerfixer on top of lisa.
Well, I'd say that's enough rambling for one day.