http://www.transhumanist.com/volume1/moravec.htm
[quote site] The best evidence about nervous system memory puts most of it in the synapses connecting the neurons. Molecular adjustments allow synapses to be in a number of distinguishable states, lets say one byte's worth. Then the 100-trillion-synapse brain would hold the equivalent 100 million megabytes.
http://library.thinkquest.org/C001501/the_saga/compare2.htm
[quote site] Our best possible guess of the average human brain's capacity would by calculating using the number of synapses connecting the neurons in the human brain. Because each of the synapses have different molecular states, we estimate each of them to be capable holding one megabyte worth of memory. Since the brain has 100-trillion-synapses, we can safely say that the average brain can hold about 100 million megabytes of memory !!!
[quote 2 ]
1999's fastest PC processor chip on the market was a 700 MHz pentium that did 4200 MIPS. By simple calculation, we can see that we would need at least 24,000 of these processors in a system to match up to the total speed of the brain !! (Which means the brain is like a 168,0000 MHz Pentium computer).