[comp.sys.mac.hardware] Mac II modifications ...

bh11+@andrew.cmu.edu (Braddock John Hathaway) (03/06/91)

I was just wondering ... what would be the effect of putting a
20MHz 68020 in a stock Mac II ... would there be a speedup or
would the chip just run cooler than before?

I realize that I am showing my hardware ignorance by asking this,
but I'm curious anyway.

Thanks,

Brad


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        conforming to its perimeter.
                Also called the silhouette of passage, this phenomenon is the
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Brad Hathaway
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jcav@ellis.uchicago.edu (john cavallino) (03/06/91)

In article <Abp4crq00Uh_M4aJxH@andrew.cmu.edu> bh11+@andrew.cmu.edu (Braddock John Hathaway) writes:
>I was just wondering ... what would be the effect of putting a
>20MHz 68020 in a stock Mac II ... would there be a speedup or
>would the chip just run cooler than before?
>
>I realize that I am showing my hardware ignorance by asking this,
>but I'm curious anyway.
>
>Thanks,
>
>Brad

The speed (mHz) at which the processor runs is determined by a crystal
oscillator, not the chip itself.  The speed rating on the chip is the
manufacturer's recommended max clock rate for that particular chip.
Putting a 20mhz 68020 in a stock mac II will run the chip at the clock rate
of a stock Mac II, which is a little under 16mhz. Sorry.

-- 
John Cavallino                      |     EMail: jcav@midway.uchicago.edu
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