A newcomer's questions ;)

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A newcomer's questions ;)

aexpert999
While trying to study the Java language to implement the second(w Symbols) assignment(first one,symbolless was a success yeah!) it came up to me to pose this general question:Looking up some specs about my macbook pro I noticed that speed of CPU is about 2.3Ghz while speed of RAM is about 1600Mhz.I recall from the Hack Computer chip implementation that clock input is the same for the CPU and the Memory module.So,my question is,is there something hidden in the specs?Something different?More generally,it is interesting to be able to read through those stuff and actually know what you r reading!And this achievement is starting to take place thanks to your book and your effort!
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Re: A newcomer's questions ;)

ybakos
Great question. My favorite explanation is here:
Clock Speed: Tell Me When It Hertz.

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Re: A newcomer's questions ;)

aexpert999
In this explanation,writer states,at some point,that clock speed is always a multiple of 33.3333.Do you know why is that?I believe it's a mathematical issue.Or not?
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Re: A newcomer's questions ;)

cadet1620
Administrator
Nothing particularly magic about 33.333 MHz except that it's 1/3 of 100 MHz. In the analog world, it's easier to triple a signal's frequency that to double it, so this is a standard frequency for oscillator modules.

Another frequence that you may see a lot is 3.579545 MHz which is the "color burst" frequency for colr TV signals. Since early computers used color TV monitors for graphic output. they had to have this frequency available and higher frequency clocks were therefore multiples of it. The original IBM PC had a 4.77(2727) MHz = (4/3 * color burst freq.) clock.

--Mark