Computer systems, controllers and controller cards used to improve disk performance, error recovery, fault tolerance, data storage and data mirroring; hard disks, magnetic read/write equipment, firmware, networking storage system, computer software, computer terminals, servers, scanners, keyboards, printers, disk drives, micro processors, microprocessor chips, touch-pads, modems, computer mouse, optical disk drives, data storage equipment, network cards, interface cards, video cards, uninterrupted power suppliers, audio cards, multiplexers, hubs, signal converters, routers, computer bridges, network switches, filters, adapters, multi-processor computers, computer mother boards, computer set-up boxes, housing, computer workstations, computer storage boxes, computer bags; computers including notebook computers, desktop computers, handheld computers; PC-TV's, computer add-on cards