## How do Megaflops and other attributes compare to today?Trying to compare MIPS, Megaflops, or even equivalent memory sizes, is fraught with questionable assumptions and "yes but -" issues. Such artefacts are very hard to compare in any meaningfull way. Nevertheless, it can be fun to just get some rough idea of the magnitudes involved.As a starting point, many people have taken a 16Mhz Intel processor as being a base equivalent to about one MIPS. Clearly one Megaflop takes more horsepower than one MIPS, but extrapolating say a 20Mhz Intel processor to be about one Megaflop is not unreasonable. ("Yes but - what about word size? What about cache and memory bandwidth?" I hear you say. Granted - but we are only doing a very rough order-of-magnitude comparison here.) Around the year 2000, we can talk about a 1 Ghz Intel laptop, (roughly equivalent to 500 Megaflops) 128 Meg of memory, and say 30 Gigs of diskspace for around $2000. In 1970 we spoke of a 6600 with around half a megaflop of compute power, 128K 60-bit words of central memory, and a Bryant disk holding the equivalent of around 75 Mbytes of 6-bit characters. (That was the big disk with the horizontal shaft holding six 1-meter platters and hydraulically actuated heads.) All if this for around $5 million, including motor generators, water-cooling, and false-floors. If we take inflation of the dollar into account, and benchmark a 1970 middle-class 4-door sedan ($3,000) to today ($24,000) then the $5 million is really around $40 million in equivalent dollars. In terms of power, (and neglecting the energy required to run the water chillers) we are talking of a 100-amp supply at 440 volts versus a brick whose output is rated at 2.5 amps/20 volts; say 44,000 watts versus 50 watts. In terms of mass, assume the central processor, disk, and power-supply (motor-generator) at 4 tons, 1 ton, and 1 ton respectively, for a total of 6 tons (neglecting printers, card-readers, tape drives, underfloor cables, sundry controllers, etc.) versus around 5 lbs for our laptop, power-brick and mouse. Given all of these tenuous and arguable assumptions, (and equivalencing a 6-bit character to an 8-bit byte for the sake of argument) we come up with the following ratios:
(An extra column was added to the table in September 2015 reflecting the appropriate values for a current smart phone, thanks to a suggestion by former colleague RRR.)
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