IIRC the Cyrix sucked #$%^. I had one that I couldn't run XP on it. I think it was an MX version.Those 386-40s were nice. In most cases, they'd outperform a 486DX/33. At one point I had a system based on the Cyrix Cx486SLC/25 - I upgraded it to a 386DX/40. Yes, it was a significant UPGRADE.