So what really is faster...3.8GHZ CPU but NB at 2000 or 3000MHZ?

[chew*]

Thank you much again, Tony. It's exactly what I wanted to see. I think I'm starting to get to know about PII. And probably you've known about it all along. :P My hypothesis regarding PII architecture from your tables above:

1. When data can be replenished from L3, K10's performance keeps increasing to NB frequency, until it reaches the same frequency as the core frequency.
2. When data needs to be fetched from system memory, increasing NB frequency alone will give diminishing returns unless memory can keep up with it. Ideally it should be [NB frequency = 2 x memory frequency] (dual-channel)

So in my imagination, a 'perfect' 955BE would be 3.2GHz core / 3.2 GHz NB / dual-channel DDR2-1600 or higher.

Does this make sense to you, or am I totally wrong?

Your theory would be wrong.

I tested equal NB to cpu ratio.......the NB must not match or exceed cpu frequency or it takes a rather large performance hit.... for whatever reason it is not happy with a 1/1 ratio......give me a few and I will show you...

Once again I hope you don't mind Tony

For the sake of saving my poor CPU I used at PH II 925 for example.....

So here we have 1/1 ratio with CPU and CPU/NB efficiency = 67656 ( result time multipled by cpu speed ) <--lower is better



And here we drop the NB down to 2600....This should be slower in theory..... efficiency = 67436 ( result time multipled by cpu speed ) <--lower is better



And here is where the Real sweetspot truly is...... efficiency = 67411 ( result time multipled by cpu speed ) <--lower is better