[Info-vax] AlphaServer DS10 470 MHz?

[Johnny Billquist]

On 2012-01-22 13.13, Johnny Billquist wrote:
> On 2012-01-22 05.37, Michael Moroney wrote:
>> MG<marcogbNO at SPAMxs4all.nl> writes:
>>
>>> An unusual occurrence, for me at least, as I was presented with the
>>> following, below:
>>
>> [470 MHz vs. 463 MHz]
>>
>> Digital exaggerated the speed ratings of some of its Alpha products
>> slightly for some (marketing, I assume) reason.
>
> The measured cycle time is 2.16 ns. How accurate do you think you can
> measure cycle time? What is the cycle time to get to 470 MHz?
> Just do the math, and realize that the measurement of cycle time can't
> be done with enough precision to get the absolute right number.

FYI: 470 MHz gives a cycle time of 2.12766 ns. 463 MHz gives a cycle 
time of 2.15983. That is a difference of 32.17 ps. 32 picoseconds is 
pretty little. Is the accuracy of the measurements enough to deal with 
such small times?

All that said, I do not know if the stated 470 MHz is actually true. 
Anyone checked the actual crystal or clock generator circuitry to see 
what is actually the frequency base?

	Johnny