Originally posted by: Fox5
Does the NB overclocking do anything for performance without an L3 cache? Only the memory controller and L3 cache are on it, and the speed of the memory controller shouldn't make any difference.
In a word, yes. It affects the overall latency of system RAM by quite a bit (as measured in cycles), along with the maximum effective memory bandwidth (though it is not bandwidth, or a lack thereof, that threatens K10-based chips . . . or at least not that I can tell). The memory controller on K8 scaled with the clockspeed of K8 processors, but since it is clocked independently on K10, then this is not the case unless the NB speed is increased proportionately to the clockspeed increased of the cores. In fact, on K8, I think the imc was never more than 200 mhz slower than the core(s).
From what I've seen, K10 could certainly use lower system memory latency, but achieving this has not been so simple due to slow NB speeds. There's a real limit to what you can do by speeding up your memory and/or tightening memory timings if the NB speed can not be increased along with the processor's clockspeed beyond a certain point.