The big benefit of SNAP for me is that currently SNAP is the only way (that I know of) of getting Win-OS/2 to reliably work on a screen size larger than 1920x1080. Which in my case is SNAP with a dual monitor setup running 3840x1080 (I don't have two monitors that will display larger than 1920x1080. I do have a single 4k monitor).
Because of AndiB's post on 4k screen sizes awhile back, I purchased a Sapphire pulse RX 550 video card (from England - the shipping was more than the card) to see if I could get it to work on my Ryzen. What I found (on the Ryzen with RX550 video card and virtual address limit = 2048) was:
1) you have to boot as CSM in order to set colors to something less than 16M. 64K colors seems to work well. 16M colors not so good.
(first screen shot - the card name shows up as LEXA for some reason). Win-OS/2 will not work
2) If you boot as UEFI you can only use 16M colors - there is no other color option and I did not get custom resolutions to work. I did not try messing with virtual address limit
3) with UEFI boot (and 16M colors) you can get Win-OS/2 to work - but not very well.
On the second screen shot you can see the screen not getting updated correctly - noticeable for example below the "Initializing" text in the grey window at the lower left of the
Visual Builder screen.
4) There are some Win-OS/2 apps, like Paint Brush, that won't work correctly at 16M colors, even with SNAP.
5) The type of video "connection" used makes a difference. Even though the RX550 video card supports both HDMI and DisplayPort, and my monitor supports both connections, 4k will only work on with a DisplayPort connection. I also tried hooking up a 4K TV via HDMI and it will not display 4K for Panorama even though the TV and video card say they support HDMI at 60 HZ. This was also true when testing with an Intel i5 8600 with integrated UHD graphics 630, which also supports HDMI, DisplayPort and VGA.
6) for the Intel (virtual address limit = 1536) I had the same issue of needing to boot CSM in order to set the colors at something other the 16M, and the resolution at something other than 640x480.
When booting CSM WIn-OS/2 will not work in seamless mode, but will work in full screen. OS/2 seemed to work correctly - although I didn't do extensive testing.
(screen shot 3)
When booting the Intel in UEFI - at 16M colors and 640x480 (the only color and resolution choice) - Win-OS/2 would work in seamless mode and full screen.
There are some points to remember:
The older Radeon video cards that will work with SNAP are probably not going to be GOP enabled - meaning they won't work unless CSM is on, and the AOS installer will not work with them. They will work fine once AOS is installed and with CSM support turned on.
Intel has removed CSM support from most of its processors by now. AMD is removing CSM support from its graphics video cards starting at the Radeon 9000, but appears to be keeping CSM for its processors, at least at this point.
I was thinking of doing this a presentation at Warpstock Little Rock if you guys think anyone would be interested.