> The 486 was the first Intel CPU to utilize a cache.

The 486 was the first Intel CPU to integrate a cache on its die (following the competing Motorola CPUs MC68020 and MC68030).

Previous Intel CPUs already utilized caches, otherwise they could not achieve 0-wait state memory access cycles.

The cheaper 80286 and 80386SX motherboards usually omitted the cache to minimize the costs, but any decent higher-end 80386DX motherboard included an external write-through cache, with a size typically between 32 kB and 64 kB, so significantly bigger than the internal 8 kB write-through cache of 80486. An 80386DX without cache could never approach its advertised speed.

Because of the small internal cache of 80486, all good 486 motherboards implemented an external L2 cache, usually with sizes between 128 kB and 256 kB, as by that time the cost of cache memory chips had diminished in comparison with that of the years of 80386.

In the beginning, write-through caches were used, as they were much easier to implement externally.

Pentium (1993) was the first Intel CPU with a write-back cache (of 16 kB), which then was also added to the Intel 486DX4 CPU (100 MHz). Then AMD made 2 kinds of 486DX4 @ 100 MHz CPUs, an early model with an 8 kB write-through cache and a late model with an 8 kB write-back cache (which had also taken the CPUID instruction from Intel Pentium). AMD's DX4 @ 133 MHz had the write-back cache extended to 16 kB, like that of Pentium (and it was rebranded as 5x86, to confuse the buyers).