Viewports always have worked with systems fullfilling DX8+ specs.
DX7 has no scissor test (DX9+ and OpenGL have it), you need to do it through clip planes and 2D office cards (totally outdated intel/sis/s3 with Pre GMA900 technology so unable to run BM Max2D anyway) just support 2 of them (one for near clip, one for far, but none left for the side. all newer support 4+)
DX7 has no scissor test (DX9+ and OpenGL have it), you need to do it through clip planes and 2D office cards (totally outdated intel/sis/s3 with Pre GMA900 technology so unable to run BM Max2D anyway) just support 2 of them (one for near clip, one for far, but none left for the side. all newer support 4+)