Looks like it'll do 1600 x 1200 x 24bit without a problem.

http://www.themacintoshguy.com/mactips/archive/tip16.shtml

I know this is old hat for a lot of you, but it might be useful for others so I'm going to go through the exercise in public . . .

. . . so please correct me when I put my foot in it.

Research results:

(((WxHxC)/8)/1024)/1024)

W = Screen width in pixels

H = Screen height in pixels

C = color depth in bits per pixel

ex.

640x480x16 = 586KB

Click to expand...

There was a caveat posted later that this formula is good only for 2D resolutions, which is fine by me . . .

Standard Definition Formats
480p - The Resolution is 704x480 pixels, sent at 60 complete frames per second.

720p - The Resolution is 1280x720 pixels, sent at 60 complete frames per second.

1080p - The Resolution is 1920x1080 pixels, sent at 60 complete frames per second.

Click to expand...

This is way it looks like I ought to, at the very least, be able to get QuickDraw accelerated 720p out of a 23 year old NuBus VidCard! 8-o

It looks like 1080p with 8% more pixels than 1600 x 1200, may be too many pixels for 6MB of VRAM . . .

. . . dunno, gotta tweak the spreadsheet to find out, I'm getting a result of 600k for the example quoted above thus far . . .

960 x 540 x 24bit ought to work just fine, as that's about 1/4 of the pixel total of 1600 x 1200 . . .

I'll call this pixel-halved 1080p/68kMLAp, for 1/2 scale, Pixel-Doubled 1080p SuperMac Spectrum/24 output.

Man, I really hope this works! [] ]'>

. . . to be continued.