kagaos

Well, basically I want to know what is the correlation between ram latency and ram frequency. Why is it you get lower latency with lower frequency (and vice versa). And for that matter, what is latency?

Thanks guys!

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jfizz84

the latency is basically the time it takes to communicate between a command u give the computer until it actually retrieves the information to do so. less timing equals faster ram and the frequency is the cycles per second so to speak of the ram. usually, the higher the frequency or rpm;s if u will the faster the information is retrieved.
cache is important too. itll save up certain information in the cache so when u request that information it has it right then and there instead of cycling thru to get it. im sure theres a more in depth thread on Overclock.net here somewhere. good luck on ur quest for knowledge

sylvanos

Seems that we are on AMD forum , i will add i heard AMD CPU use better low latency than high frequency

kagaos

Right-o. So my question now is, why is it you can get more "RPM's" but it takes you longer to retrieve something? I mean to me it would seem like it should be higher frequency = lower latency, yet it is quite the opposite. Why?

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jfizz84

yea just remember tho general rule of thumb is higher frequency lower the timings, even tho that does not neccessarily mean go for the higest frequency as its important to have a good equal balance in my opinion

jfizz84

it usually holds tru for the most part excpet when u jummp from say ddr1 ram, to ddr2, or ddr3. then it fluctuates a wee bit more. also take into account the voltage. i was told anyways the more important one is the cas latency and the timings are kind of a ball parkish figure, altho not sure how true

faisal

it is necessary increase vdimm if we play tight timing?
what is means by 4-4-4-12 (the bold ones)

typoknig

A good rule of thumb is that every ONE decrease of CL timings is roughly equal to a frequency increase of 125MHz. I read a very good article on this subject on Tomshardware once (tables and everything) but I am unable to locate it now. The article I am writing about was testing with DDR2 RAM but I put his figures to the test with my DDR3 RAM and they seem pretty accurate still.