While I realize that L1 and L2 cache are different, generally speaking, the difference was where it was at, and the speed it was accessed. You wanted your L1 cache (originally known as the "on-chip" cache) to be used first because it was right next to the cpu, and hence most quickly accessible, assuming it was large enough, without having to go and search for data/instructions (at a much slower speed) at the L2 cache, which was traditionally on the motherboard. That was why the Cyrix 486 chip was so much slower than its Intel equivalent--the Cyrix version had only 1KB of L! cache; the original Intel 486 had 8KB. When AMD put an "L2" cache on the chip too, yes the cpu would store, and search, first on the L1, but the overflow data on the L2 was essentially accessible at the same speed as the L1, so from an external perspective, L1 =~ L2. With the Compaq laptops that were sold with a K6-2, IF Compaq had put L2 cache on the motherboard (I don't know for sure whether they did or not), if you replace the K6-2 with either a k6-2+ or a K6-III+, the L2 effectively becomes "L3 cache", an animal that never existed before, and "is icing on the cake"!
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