cpu oc and ram syncro

[ppdemo]

hi all, i need help about the next:
first of all i have a i7 4790k OC at 4.5ghz and a 2400 cas11-13-13-31-2T gskill ram with xmp profile enabled so my question is how i sync the ram with the OC cpu.
should i set timings and else, manually or directly OC a little more the ram? i ask this because think that i have not still a correct synchronization between cpu and ram, this although xmp profile is like i have set in bios. i hope you answer regards my friends...

 

[Yuriman]

Not sure what you mean by "correct synchronization".

 

[ppdemo]

sorry, ratio 1:1 cpu-z show me fsb ratio 1:9. isn't it very far?

 

[Yuriman]

There's no such thing as FSB anymore, memory controllers were moved on-die more than a decade ago, so there's nothing to synchronize with.

 

[Tuna-Fish]

Proper RAM/CPU sync was something that mattered quite a bit way back when all memory transfers went over the FSB. That no longer happens -- these days, the memory has it's very own dedicated link from the memory controller on the CPU to the ram. The systems are independent, best results are found simply when both the ram and the cpu are running as fast as possible.

 

[LTC8K6]

sorry, ratio 1:1 cpu-z show me fsb ratio 1:9. isn't it very far?

That's normal and does not need to be corrected.

 

[LTC8K6]

1:31 With a Kaby Lake chip:

https://forums.anandtech.com/thread...-now-with-delid.2493250/page-14#post-38679104

 

[2is]

As mentioned, this was only an issue back when there was an FSB. What is sometimes referred to as a FSB today is nothing more then a base, or reference clock. It doesn't actually do anything, it's just a reference clock used to calculate the clock speeds of the CPU/RAM etc.

 

[ppdemo]

thank all now everything is more clearer to me but i have another doubt maybe this has nothing related , but this is:
dram ratio 100:100 / 100:133 or auto in bios. which should i choose?

 

[Yuriman]

Whichever one results in your RAM running at the correct frequency. RAM is usually very sensitive to overclocks and even going slightly higher than its rated may result in bluescreens and instability.

 

[ppdemo]

ok thank very much all of you. lucky guys!