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• $5995
1984 •

IBM PC AT

An 80286 CPU running at 6 MHz with 1 wait state
256KB or 512KB RAM on the motherboard
A 16 bit bus which became known as the ISA bus
Seven DMA channels
Sixteen levels of interrupts
Configuration stored using a battery-backed CMOS RAM
Real-time clock (also battery-backed)
84 key keyboard with indicator lights synchronized with the machine
A keylock to disable the keyboard when the operator was not present
A larger power supply capable of providing power to two hard drives
One 1.2MB high density 5.25″ diskette drive
20MB hard drive (supplied as standard in model 099 only)

IBM Color Graphics Adapter or Enhanced Graphics Adapter
128KB Memory Expansion Option (card providing RAM between 512KB and 640KB) (photo)
512KB Memory Expansion Option (card providing extended memory) (photo)
Standard double density floppy drives