Editing Cyrix (section)

=== 486 ===

Its early CPU products included the [[486SLC]] and [[486DLC]], released in 1992, which, despite their names, were pin-compatible with the 386SX and DX, respectively. While they added an on-chip L1 cache and the 486 instruction set, performance-wise, they were somewhere between the 386 and the [[Intel 80486|486]]. The chips were mostly used as upgrades by end users looking to improve performance of an aging 386 and especially by dealers, who by changing the CPU could turn slow-selling 386 boards into budget 486 boards. The chips were widely criticized in product reviews for not offering the performance suggested by their names, and for the confusion caused by their naming similarity with [[Intel]]'s SL line and [[IBM]]'s [[386SLC|SLC]] line of CPUs, neither of which was related to Cyrix's SLC. The chips did see use in very low-cost PC clones and in laptops.

Cyrix would later release the Cyrix 486SRX2 and 486DRX2, which were essentially clock-doubled versions of the SLC and DLC, marketed exclusively to consumers as 386-to-486 upgrades. Unlike the SLC/DLC, these chips contained internal cache coherency circuitry which made the chips compatible with older 386 motherboards that did not have extra circuitry or BIOS routines to keep the cache current.

Eventually, Cyrix was able to release the [[Cyrix Cx486#Cx486S|Cyrix Cx486S]] and later [[Cyrix Cx486#Cx486DX|Cyrix Cx486DX]] that was pin-compatible with its Intel 486 counterparts. However, the chips were later to market than [[Advanced Micro Devices|AMD]]'s 486s and benchmarked slightly slower than AMD and Intel counterparts, which relegated them to the budget and upgrade market. While AMD had been able to sell some of its 486s to large [[Original equipment manufacturer|OEM]]s, notably [[Acer (company)|Acer]] and [[Compaq]], Cyrix had not. The Cyrix chips did gain some following with upgraders, as their 50-, 66-, and 80&nbsp;MHz 486 CPUs ran at 5&nbsp;V, rather than the 3.3&nbsp;V used by AMD, making the Cyrix chips usable as upgrades in early 486 motherboards.