pc power supplies
pc power supplies(Redirected from PC/AT)The IBM Personal Computer/AT (IBM 5170), more commonly known as the IBM AT and also sometimes called the PC AT or PC/AT, was IBM's second-generation PC, designed around the Intel 80286 microprocessor running at 6 MHz and released in 1984. Because the AT used various technologies that were rare at the time in personal computers, the name AT originally stood for Advanced Technology, and indeed, the Intel 80286 processor used in the AT supported Protected mode. Later, IBM released a version of the AT running at 8 MHz. AT features16-bit ISA bus - The AT motherboard had a 16-bit data bus and supported both 8-bit PC-style expansion cards as well as the new 16-bit AT expansion cards for the 8028615 IRQs and 7 DMA channels, expanded from 8 IRQs and 4 DMA channels for the PC. IRQ 8-15 are cascaded through IRQ 2, which leaves 15 active instead of 16. PowerOn. Similarly, DMA channel 4 is reserved for cascading 0-3 leaving 7 channels active. 16 MiB maximum memory supported by the 24-bit address bus, compared to the PC's 640 kiBbattery backed Real-time clock on motherboard with 50 bytes CMOS memory available for power-off storage of BIOS parameters. (the basic PC had required either manual setting of its software clock using Time and Date commands, or the addition of an accessory expansion card with real-time clock, to avoid the default 01-01-80 file date)84-key AT keyboard layout - the "84th key" being <SysRq> i. e. Home paint supplies discount diabetic supplies plumbing supply cheap computer supplies cheap computer supply barbershop supplies supply chain management education hp printer power supplies power cords used power generator invacare power wheel chair puls power supply merchant services business services cash international loan payday services web design service telemarketing services email hosting services carpet cleaning services international cell phone service 24 hour answering service voice mail service prepaid wireless phone service cheap broadband service debt settlement service internet service provider hosting satellite service dialup service christian dating online service seattle dating services answering service business nextel phone service magazine printing services free on line dating service internet business services customer service contact center software broadband internet service for business online meeting service cable dsl service best internet dating service credit reporting service criminal background check services database hosting services |