DDR3 - Why is it so dishonest?

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I'm in the market for my first DDR3 RAM - in fact I've just bought some and returned it because it didn't peform as advertised.

Now when I bought DDR or DDR2 and it was advertised at CL5 @ 1066MHz @ 2.0V (for example), I plugged it in and it was CL5 at 1066Mhz.

I new that if I wanted to squeeze some extra MHz or tighten the timings I might have to play around with the BIOS settings and voltages etc. But that was my choice, part of being an enthusiast and overclocking my kit.

But, if I understand what I've been told and read, DDR3 isn't sold anything like this. The advertised setting are overclocked (because I'm told the only JEDEC standard for DDR3 is 9-9-9-24 @ 1333) and to acheive it I will have to play around with my BIOS, experimenting with parameters in the hope of finding the ones that will work. The real challenge is there is no guarantee that it will work at advertised and all the experimenting in the world won't help. To confound this the manufacturers don't even provide a set of paraemeters to use, even as a starting point.

It just seems really iffy that the manufacturers are selling stuff which it's customers have to put in a lot of advanced configuration just to get working at the advertised spec.

Or am I missing something?

Cheers,

Nigel
 
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That's one concern with the build I've ordered. The SPD, or XMP (which isn't supported by older motherboards), should just have the best timings the memory can achieve for all supported frequencies. Hence plug it in and it runs optimally.

Maybe it does do this with newer XMP motherboards, but can't be sure until I try it.

I've ordered the same G.Skill 1600 C7 memory you sent back, but I'll be using a P55 motherboard at least. I'm intending to run this at 1333MHz, and will be a little bit miffed if it defaults to 9-9-9-24.
 
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JEDEC standard for DDR2 was 800mhz, 5-5-5-15 I believe so anything faster than that (e.g. 1066) was technically an overclock. Your problems with DDR3 makes me think it must be too new for the manufacturers to establish the best binning patterns.

That said, I did get a set of 1066 DDR2 that wouldn't work at the specified timings once. It's not really on tbh, I guess it's a grey area.
 
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The speeds they quote, are they not what is it RATED to run at. Not what it actually runs at when you plug it in. Unless you enable the XMP profile. The RAM doesn't know what it's meant to run at when you buy it, unless you tell it what to do.
 
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Unless you enable the XMP profile.

(1) If you can

(2) If there is one

(3) The manufacturers don't make it clear whether there advertised settings are in XMP, EPP, AOD download profile or what - pure guess work.

Sometimes they don't advertise that it is for a specific chipset until either you receive it and it has a big 'Designed for i5' sticker on it or you contact the manufacturers technical support and they tell you.

I wouldn't be so bad if the configuration involved just the main 5 parameters and DDR voltage but it seems you have to play around with all the obscure parameters and other voltages (NB and SB).

And it wouldn't be so bad if the manufacturers supplied a set of settings that are likely to work (or at least a good start) rather than leaving the customer in the total dark.

Cheers,

Nigel
 
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I'm not sure the issue you're upset about exists. The ram was tested (we assume, anyway) and found to run at specified speeds and voltages in whatever system they were using. I you buy 2000mhz ram and a processor which through bad luck has a really crap imc, it won't run this fast. Same as the old(er) days when my 1066mhz ram flatly refused to run at this speed on a G35 chipset. It was the board at fault, it ran at 1150 when I got a new motherboard.

The ratings are what the ram is capable of. If the rest of the system isn't, then you can't really blame the people who made the ram. If you bought dual channel 1.65V ddr3 to use in an x58 board, I'll have to assume you did no research whatsoever I'm afraid.

But then, I'm biased, as the above aside I've never had problems with ram running at the speed it says it will do. I'm sorry you're having less luck
 
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Meh?

THe DDR3 G-Skill 1600mhz cl7 I bought ran at something along the lines of 10 10 10 24 when plugged in.

I then opened the bios, enabled the XMP profile and it's now 7-7-7-24. Dammed if I can tell the difference but thats what it's now running at. Also quite easy to change to other settings.

I paid more than the norm for the motherboard mind you so perhaps it's just easier with this one.
 
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I wouldn't be so bad if the configuration involved just the main 5 parameters and DDR voltage but it seems you have to play around with all the obscure parameters and other voltages (NB and SB).

And it wouldn't be so bad if the manufacturers supplied a set of settings that are likely to work (or at least a good start) rather than leaving the customer in the total dark.

The settings the RAM is rated to run at is actually on the stick. Just plug those into the BIOS to begin with. Those are timings, are you use maths within the BIOS to calculate the correct multiplier.
 
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i have the exact same problem, my memory defaults to 1066mhz 7-7-7-24 in auto,its rated to 1600mhz 7-7-7-24 theres no xmp thing in my bios, also cant stabilize it at 1333mhz either , ican set it to a divider of 3 4 or 5 , 5 giving me 1333mhz settings but not stable settings, its very misleading indeed, im thinking of rma and get a set thats got 1333mhz as default, anyone know of such a set?
 
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The settings the RAM is rated to run at is actually on the stick. Just plug those into the BIOS to begin with. Those are timings, are you use maths within the BIOS to calculate the correct multiplier.


That's correct, with an FSB, the RAM generally ran at the same frequency (ignoring the DDR clock speed) or as a multiple, fraction or in a ration relative to the FSB.

For example, the Default FSB speed of an E6750 CPU is 1333, that means that RAM running at its default speed will be at 667Mhz until you overclock it (667 is half of 1333, it's technically the same frequency when you take DDR in to account).

Until you overclock your CPU's FSB, the RAM's clock speed will be what ever the CPU's FSB is.

So even if you had DDR2 800/1066Mhz RAM it'll only ever be running at the same speed as the FSB, which in this case is 667.

Overclock the CPU via the FSB and your RAM will be operating at a higher frequency.

I've never known RAM that has a clockspeed rated higher than the FSB of my CPU to run at its rated speed. It ALWAYS has ran at the FSB clock for me.
 
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JEDEC standards have always had a lower limit than the RAM available. Manufacturers state the RAM will run at their rated speed, if not limited by other factors.

ie PC3200 was the highest DDR rating, though manufacturers had PC4400, I think PC6400 is the highest DDR2 rating etc
 
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I think the memory manufacturers are just responding to the market. Higher than JDEC rated DDR3 RAM has come to market much quicker than it ever did with DDR2 and more so DDR.

In the past, users have manually pushed their good quality RAM past its specified rating on good quality motherboards - that's the art of overclocking!

The manufacturers seem to have responded to this by releasing RAM at these elevated ratings faster than the chipset manufacturers can improve their chipsets to 'officially' cope with these speeds - hence you are buying 'overclocked' sets of memory that need to be manually configured in the BIOS!
 
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How do you find out what they are?

Obviously, the 7-7-7-24 @ 1.65V is advertised no problem with those.

But how do find out what all the other parameters and voltages would be set to?

Cheers,

Nigel

Well, for a start, you having timings and voltage on the actual stick. Like you said, 7-7-7-24 @ 1.65V. That's two things sorted.

And as for speed to run at, well, you know what you bought right? Say it's 1600MHz RAM.

You need to use the FSB/BCLK in your BIOS, and multiply it by the RAM multiplier. It's just like basic maths.

For example, the default BCLK on my i7 was 133MHz. The standard RAM multiplier was around 10x is I remember. So, when you plug the RAM in, it will run at 133MHz x 10 = 1330MHz @ 1.5V (standard voltages).

The RAM is not clever. No one has told it what to do. It will only do, what you tell it to do.
 
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You need to use the FSB/BCLK in your BIOS, and multiply it by the RAM multiplier. It's just like basic maths.

Yep I know that - setting the memory speed to 1600MHz is childsplay.

What I'm talking about is the host of extra parameters, such as

TwTr Command Delay
Trfe
Write Recovery Time
Precharge Time
Row Cycle Time
RAS to RAS Delay

Haven't got a clue what they should be set to. Some people say they are not important, but when I visited the GSkill forum there many 'problem threads' where the advice involved playing about with these particularly Trfe.

Also voltages beyond the obvious DDR such as SB and NB.

I fully accept that it could be that my motherboard isn't up to it, but still contend that if a product is sold at 7-7-7-24 then the manu should list the settings needed to acheive this - and if after trying them, it still doesn't work I could concede that it is my MoBo or marginal memory. But instead the customer is left guessing what settings should be used and so when it fails it is not possible to tell whether it is settings, voltages, MoBo or memory that is at fault.

Cheers,

Nigel
 
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So at the risk of ULTIMATE FAIL :p, when I plug my 1600MHz 7-7-7-24 DDR3 memory into my Gigabyte P55M-UD2 motherboard, running at standard 133 BCLK, what will the default timings be at 1333MHz?
 
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ok, thanks. Seeing as I'm intending to keep things default speed for a while, I may change my order for some 1333 C6 memory or similar. Cheers!
 
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