Question on Cas Latency ratings on DDR2 Mamory

Roberty

Roberty

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OK, It's upgrade time again for me. I currently have a FX-60 and Ultra-D combo and I'm going to upgrade to an X2-6000 AM2 system. I understand on the DDR memory that using lower timings is always a little better/faster but I'm new to all of the DDR2 stuff. Looking at Newegg, There are a shitload of different memory for the DDR2 2X1gb kits that I'm interested in and my question is this:

Will a lower Cas Latency such as a 4-4-4-12 be faster than 5-5-5-15 like it would be using DDR memory or is it different with the DDR2/AM2 stuff? This is assuming that both are the same speed rating such as 6400.

I probably won't be doing much overclocking with this system BTW.
 
lower timings at a given speed are always better

for ddr2 being faster/slower than ddr1.. it depends on what you're doing. while the timings are higher, don't forget that the speed is approximately doubled. timings are measured in clock cycles, so if the clock cycle is faster... more clocks isn't always slower ;)
 
That's what I thought but I just wanted to make sure before spending the $$. Thanks for the reply Eclipse - I appreciate it bro'.
 
np

though keep in mind the differences between value ram and performance memory really come down to how well the overclock. memory timings and speed have a surprisingly small effect on performance. check this out ;)

timings.png

hq.png



but if you're benching...
1m.png
 
wow hardly much reason to worry about latency. Hard to make myself believe that though as I'm coming from the AMD/DDR world of "must have low latency". I'm choosing my first set of DDR2 ram though... can't decide between 5300 and 6400 for an E6600 - due to some of the corsair brand 6400 ram going up in price. I may look at some of the cl 5 ram now though... i think
 
going for intel is a good choice. corsair xms2 is good. i got the cas4's and there great.
 
Yeah memory timings are one of those things many inexperienced people worry over way too often. Some people think timings make all the difference in the world, when in fact they make a very small difference.

This is why, when you are looking to buy memory, you should look at what you need to do and how high you need the memory to go, not so much how low the timings are as some people do.

The difference between 4-4-4-12 and 5-5-5-15 is actually very small. Anyways, most 5-5-5-15 timing sticks, will most often easily do 4-4-4-12 if you set it in bios. So to me it seems like a moot point.
 
Simple answer is..... tighter and faster is always better. There is no arguing with that fact, posting that it really doesn't matter is usually just to make someone feel better about thier choice of low end memory. You get different answers to this question on different forums, go to an overclocking forum and you won't hear "it really doesn't matter". I think it's up to the individual to decide if it's worth the cost to them for what they intend to do.
 
So - excuse the hijacking but do I want "EPP". What the hell is EPP? And what about 1T vs 2T? I'm thinking of an Asus P5B Plus, an E6600 CPU, and whatever ram I end up with. I would be extremely happy if I hit 400*8 for 3.2ghz. I have no plans on really running the fsb past 400 mhz.

With that in mind, does EPP do anything for me. Are you down with EPP? Do newer machines (Intel specifically) have any trouble running the ram at 1T? What about with 4 Sticks?
 
your board doesn't support EPP nor 1T. you can get ram that "supports" those and it'll run fine, but don't waste the money getting some if there is a better deal without it.

1T is a memory controller thing more than memory anyway :D
 
there are boards now that don't support 1T ? What I was wondering was if 1T vs 2T made a difference with DDR2 ram? It definitely makes a noticable difference with Socket 939 + DDR
 
basically every board with an intel chipset doesn't have an option for command rate. it's just set to 2T.

with the boards that do have it, you normally can't get much over 400-500mhz... and most decent ddr2 should break that easily


there is a difference, but it's a moot point cause it's usually faster to run high clocks
 
seanmcd said:
there are boards now that don't support 1T ? What I was wondering was if 1T vs 2T made a difference with DDR2 ram? It definitely makes a noticable difference with Socket 939 + DDR
Click to expand...

I've been doing a lot of playing around recently with my E6600 / 2x 1Gb Corsair 8500C5D's and I've run the gamut from 9x385 to 7X475 (my cpu / mobo limits) for memory settings of 770MHz 4-3-3-10-1T (sync'ed and linked) all the way to 1200MHz 5-5-5-18-2T (unlinked) and I gotta say that I was completely underwhelmed by the differences. I don't have the hard numbers in front of me, but I tested using Everest 4 Ultimate memory benchmarks, and 3DMark06 suite.

The differences were small enough to make me think "Jeez, it really doesn't matter where I run this, the performance differences won't be able to be detected by the naked eye to me".

If you are trying to maximize a particular benchmark for online comparison, then it may make a difference, but I am just looking for a everyday stable, fast setup for surfing-gaming-work projects.
 
Teknokid said:
try same speed with 1t and 2t.
Click to expand...

If you were speaking to me, did you read all of what I typed?

To quote "...I've run the gamut from 9x385 to 7X475 (my cpu / mobo limits) for memory settings of 770MHz 4-3-3-10-1T (sync'ed and linked) all the way to 1200MHz 5-5-5-18-2T (unlinked)..."

"Bold'ed" for your clarification.

1T was only good up to about 800MHz for me, before it would prevent me from POST'ing. 1T is not the magic number that some people would lead others to believe.
 
settle down ladies - Only asking these questions as it USED to be a deciding factor with ram. I'm inquiring about DDR2 and the latest systems. Thanks for all the reports.
 
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