But what about the processing power? Osbourne 1 was sporting a Z80 CPU, running at a stunning frequency of 4.0 MHz. You cannot compare the different architectures directly, but iPad’s CPU is a dual core A5, clocked at up to 1 GHz. That’s approximately three hundred times more, not counting in the vastly superior architecture.
Z80 CPU was supported by whooping 64KB of system memory. Surprisingly, it was enough to run databases, word processors and complex, professional software. Today’s iPad is equipped with 512MB of RAM (roughly one thousand times more), and some reviewers complain it’s a bit on the low side."
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