I'm not totally sure what you're trying to say. Even back in the days of "software rendering" - or on those embedded systems that you're describing - you still had a piece of graphics hardware that converted the frame buffer into whatever got spit out to the monitor, so I don't think this is meaningful, really.

What's meant by software rendering is really software rasterization - the process of taking the triangles, textures, etc. of the scene and turning those into the pixels that eventually make their way to the screen. You can still do that in software on the CPU today without touching the GPU, even the integrated one. At that point you hand it off to the hardware to make its way to the screen, sure, but it's only an implementation detail that makes that different from handing 0xA0000000 over to the VGA card. The interesting part of the process, and the results, are functionally the same.