Transistors are getting cheaper and cheaper and it only takes some 0.5 million transistors to make a very high quality CPU
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Essentially impossible to increase clock speed and so must exploit increasing transistor density in figure of merit (1/f)2-4
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Already we build chips with some factor of ten more transistors than this and this is used for "automatic" instruction level parallelism.
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This corresponds to parallelism in "innermost loops"
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However getting much more speedup than this requires use of "outer loop" or data parallelism.
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Actually memory bandwidth is an essential problem in any computer as doing more computations per second requires accessing more memory cells per second!
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Harder for sequential than parallel computers
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Data locality is unifying concept!
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