Under/Over-clocking the CPU-NB

[Fike]

I know that when you raise the HTT, the memory speed goes with it. That is why you then use a memory divider. Does the CPU-NB speed also increase? Put another way, if I am overclocking 20% at the HTT, should I underclock the HTT by 20%--say to 800 MHz?

--or--

If the HTT is moved from default of 200 to 240, does that mean that the NB-CPU speed has also moved up by 20% to 1200?

 

[Fike]

bimp

 

[Fike]

maybe....bump....again....

 

[betasub]

Yes, the CPU-NB link is based of the HTT base (default 200MHz), and will typically have a 5x (or 4x) multiplier. If you are overclocking the HTT 20% (from 200 to 240) then dropping the HTT multiplier by one step (from 5x to 4x) should keep the CU-NB link within specified limits. It may work overclocked, but there's no real world benefit, because even 600MHz HTT (3x200) isn't a limit for CPU-NB transfers i.e. there's no performance penalty from "underclocking" the CPU-NB link.

 

[Fike]

Thanks. that is very helpful. I am wondering if perhaps throttling it back might help me get the stability to get another 100 MHz.