[vcf-midatlantic] What limited the C64's CPU to ~ 1 MHz?

RETRO Innovations go4retro at go4retro.com
Thu Mar 23 13:14:13 EDT 2017

In my opinion, the 64 ran at 1MHz, because Jack did not have interest in 
investments needed to make the chip faster.  He wanted it cheap and 

In some respects, this aligned with the original MOS goal.  CPUs for the 
masses, cheap.  I am sure the HW guys would have loved to do more R&D, 
but MOS' tech was "good enough" to support the company, and that's what 
Jack focused on.

I believe there are -2 and -3 MOS NMOS units and had been for some time, 
but Jack didn't need fast, he needed fast enough and that was it.  
Running at 2MHz would have required static RAM or faster DRAM, so 1MHz 
(essentially 2MHz due to the CPU/GPU bus sharing) was fast enough.


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