In contrast to the TI SXL, the UMC Green is the fastest "true" 486 processor by a long-shot (clock-for-clock). It does integer division in 7 clock cycles vs 20+ on Intel/AMD 486s and has other improvements too. Sadly, it was swiftly crushed due to legal disputes with Intel.

https://youtu.be/1Rj1B4M6yXM