Cyrix Corp has duly expanded its Upgrade Microprocessor family with the Cx486SRx2, aimed at users of 16MHz, 20MHz and 25MHz 80386SX systems: the new SX version of the Upgrade family implements the same microprocessor core used in the Cx486DRx2, and offers features that improve performance by up to 70% clock-doubling circuitry, 1Kb on-chip cache, improved input-output operation of data, single-cycle execution and a hardware-implemented integer multiplier; a clip-on device, co-developed with Augat Inc snaps the Cx486SRx2 onto the existing 80386SX microprocessor, disabling the original chip and enabling the Cx486SRx2 to take over all the microprocessor functions – but it is not suitable for notebooks as it requires 1 spacing to accommodate the Upgrade and heat sink, and allow for proper airflow; Cx486SRx2 25/50, for upgrading 25MHz systems, is $300 retail, Cx486SRx2 20/40, for 16MHz or 20MHz systems is $270.
