I was going to correct you, and say the DX had a coprocessor, but the SX did not. Apparently, that’s incorrect, and the difference is bus width. However, at t

I was going to correct you, and say the DX had a coprocessor, but the SX did not. Apparently, that’s incorrect, and the difference is bus width. However, at the end of its life, my 386 motherboard was running one of these at 100MHz, with a coprocessor on the daughterboard in the main CPU socket: https://en.m.wikipedia.org/wiki/Evergreen_Technologies https://en.m.wikipedia.org/wiki/Evergreen_Technologies (I think I had an IBM 486, not a Cyrix, fwiw.) Sadly, I’d moved to Linux at that point, and the processor needed a special MSDOS binary to flip into 100MHz mode after boot. Even with the handicap, it booted into X11 + enlightenment at 25MHz (or maybe 33MHz) faster than it could boot into Windows 3.11 at 100MHz.