The Serpent Rider wrote:

I think the main reason of Win 9x of sluggishness on 486s is I/O speed, not CPU itself. Can be compensated with flash HDD and/or good PCI IDE card.

It's rather memory and cache bandwidth: 32-bit 33MHz vs. 64-bit 66MHz. A good PCI IDE card isn't of much use if actual memory read speed is about 30MB/s even though the PCI bus itself is theoretically capable of 133MB/s. However if the system bus is overclocked to 66MHz with EDO memory installed, we have about 80MB/s read speed which makes a huge difference.