I am also looking for these files.

So the Super Spectrum card is supposed to have a mode switching program, similar to what ATI had. It would help explain what the card is fully capable of doing. All I've found is the Genoa Spectrum programming manual on archive.org, Ralph's interrupt list has additional programming information (more for the Genoa SuperEGA) and then found here is a driver for a variant of the SuperEGA. I think one could write a replacement utility/driver, as the Super Spectrum is probably somewhere between the Spectrum and Spectra/SuperEGA, so it could be that it is mostly compatible design, and that info will give us most of what it can do. There is also a boxed copy of the Spectrum on the auction site, but it is alot of money to get a disk for the older card that might not accurately reflect the newer one. I'd hope something might be found, but I was kind of thinking that I might have to review the ports and disassemble the SuperEGA mode switching program, since there doesn't seem to be any other reference to the exact driver out there.

I have the plain Spectrum 4600 (full length) and 4600N (half length) but no software. I saw that archive.org manual and it seems like the mode switching thing isn't really necessary. Except maybe to fool programs into using Hercules or CGA if they don't have a way to manually specify. I am mainly interested in the Windows 3.x drivers in hopes that it would support the 640x200 Plantronics mode.

Is the Super Spectrum EGA just the Spectrum with additional support for EGA? Does it have a BIOS?

The Super Spectrum does not provide EGA -- it does not have a BIOS. It is a more integrated version of the Spectrum 4600, and also has a plantronics mode, and references some kind of "2nd card" support. It is otherwise just a regular souped up CGA compatible card. I had tried to also find the drivers by looking for the windows drivers, and I could not find anything there either.

Yes, agree that the software mode switching is not needed in my testing, and you are given jumpers to set the default modes in the worst case. I just want to know what the Super Spectrum supposedly offers over the Spectrum, and maybe the driver disk would have a clue.

This site
https://www.video-drivers.com/drivers/67/67014.htm

Seems to suggest there was something passed around as a Windows CGA driver for the Genoa cards, but when you look closely, it is easily identified as the MS Win3.x generic CGA driver. It is possible that is all that Genoa uploaded to their FTP, as they identify the distribution for Win3.x on their website. I think that is all it is because by the time Win3.x was popular, no one really bothered with plantronics, and anything older like DOS or Win2.x/Win1.x probably didn't matter anymore. So I don't think there ever was a proper driver available on the net. That pretty much means getting a hold of a disk to be sure. But as history has seen so far, this disk is very unlikely to be anything special. Still wish I knew what the Super Spectrum really did.