From searching those threads so far....
It's the craptacular S3/ATI Rage series! You win S3/ATI!:
S3 Savage 4
ATI Rage series of graphics cards
Since DosBox is set to Surface as default, it's odd that Dosbox has to use WinDib for these chipsets.. I'd understand if DosBox was set to Overlay,OGL,Direct3D....but surface? WTF.
Anyone with these chipsets know if the latest drivers fix this SDL issue? If so then it's be an easy "fix" to add to the DosBox readme for people to upgrade to the latest drivers for those chipsets. Since these video cards are so old we would probably should specify working driver versions....this is assuming that an updated driver fixes the issue.