Confusing, but 386SX vs 386DX had nothing to do with math coprocessors. That was only on the 486DX which had a math coprocessor vs 486SX which did not. https:

Confusing, but 386SX vs 386DX had nothing to do with math coprocessors. That was only on the 486DX which had a math coprocessor vs 486SX which did not. https://dfarq.homeip.net/386sx-vs-386dx-a-misunderstood-difference/ https://dfarq.homeip.net/386sx-vs-386dx-a-misunderstood-diff...