XMP does not work for DZ77GA-70K and CMZ32GX3M4A1866C9

[Stabilitronas]

Hi everyone,

 

so I've got an Intel DZ77GA-70K motherboard (with newest BIOS) and CMZ32GX3M4A1866C9 kit. The problem is, none of the XMP profiles work for me. If I try to set one, PC usually doesn't even beep; it just restarts over and over until MB notices something is wrong and sets RAM to default configuration — that is, 1333MHz.

 

Then I made an experiment: I set RAM profile to 1600MHz and then changed memory multiplier from 12 to 10, so the RAM operates at 1333MHz, but with all the voltages and timings as per XMP profile. And guess what? No luck.

 

After spending a while browsing BIOS settings, I noticed one thing: some of the RAM timings of the default preset are very different than XMP ones. For example:

 

tRFC: 174 (1333MHz) vs 88 (1600MHz);

tRC: 15 vs. 38;

tFAW: 20 vs 26;

... and so on.

 

Unfortunately, I have no idea what they do. I'm only familiar with the most popular ones, that is, CL, tRCD, tRP and tRAS.

 

And then I made another experiment: I loaded 1600MHz XMP profile, left voltages in touch (DRAM voltage 1.65V and System agent voltage 1.05V), but then set the timings as they are in default BIOS mode, except those four most popular ones, which I set to 9-10-9-27, as per specification. And it boots! :)

 

http://s7.postimg.org/934qzoivf/Ram_works.png

 

Apparently, something is wrong with the timings that I have no idea what they do and thus can't set to proper values.

 

Unfortunately, the same trick does not work with 1866MHz profile. Which is my goal. Could anyone please help me to reach it?..

[Stabilitronas]

An update: sorry, the trick works with 1866MHz. PC boots. But those mysterious timings still bugs me. Aren't my RAM performance compromised?..

[peanutz94]

After spending a while browsing BIOS settings, I noticed one thing: some of the RAM timings of the default preset are very different than XMP ones. For example:

 

tRFC: 174 (1333MHz) vs 88 (1600MHz);

tRC: 15 vs. 38;

tFAW: 20 vs 26;

... and so on.

 

Unfortunately, I have no idea what they do. I'm only familiar with the most popular ones, that is, CL, tRCD, tRP and tRAS.

The secondary timings are best left on AUTO. Set the first four and let the MB set the rest. It's changing because your changing speeds. 1333,1600,and 1866 will all have different settings.

[Stabilitronas]

But this is the problem — if I let MB decide, it sets the timings wrong...

[Ultima95]

I have the same motherboard and processor -- and the same problems despite I am using a different kit (CMD16GX3M2A1866C9)

 

But I tried your solution, minus changing voltages (here it wont boot that way) but I did the same trick with the rest, the modules have the same basic timings.

 

And so far worked, cannot tell yet if it is stable, once I am sure I will post again.

[peanutz94]

There is no need to mess with the secondary timings. If your system is not stable at the advertized settings then you either have a bad set of memory or the MB BIOS is not adjusting them correctly.

 

If yu would like to replace the ram to rule out one or the other , then just use the link on the left to request an RMA.

[Nec_V20]

With regard to memory "speed" it is a case of swings and roundabouts. If one looks at increasing the DRAM frequency at some point one has to increase the timings simply because of the DRAM latencies which have - individually - a minimum below which one just cannot go.

 

Another thing to consider - which I almost never see mentioned - is the actual distances on the motherboard the signals have to travel.

 

Signals have to travel the distance and return within a very narrow time frame and those signals have to reach the components and return in the right order. One main factor influencing this is distance. Another factor is the conductivity of the material and how that material's conductivity is influenced by temperature.

 

The effects of this are minuscule - until one starts increasing the frequency of the usage of a bus. At some point a limit is reached. A motherboard might be specified for a certain "speed" but this assumes that everything during the production process has gone absolutely perfectly - differences to be measured in atoms can make the difference between yea and nay.

 

There is of course a "bugger factor" which is the DRAM refresh instruction which can also collide with settings irrespective of the validity of those settings just due to the strobe effect - i.e. the refresh coincides with some instruction sent to the RAM or some instruction which was not received from the RAM which results in a BSOD because the RAM refresh happens and coincides at the level below the HAL. The refresh ALWAYS has precedence over anything else.

 

To increase the DRAM frequency beyond a certain point one has to increase the voltage and of course that just introduces more heat and it might not be enough to compensate for the other factors.

 

So with interacting computer components there comes a point where the "should be able to" intersects with the "will be able to".

 

No one component is to blame, it is the interaction of the components which has to be pretty close to perfect for the "should" and the "will" to coincide for the higher performance to be realised.

 

Scottie's famous admonition to Kirk should be borne in mind, "Ye canna change the laws of physics".

 

The DRAM timings are plain and simply instructions for components to do NOTHING for a certain period of time before they try to send a signal again. This is why I talked about swings and roundabouts with regard to "speed" at the beginning of the post.

 

Let me put this another way. Over thirty years ago I worked in a concrete factory doing piecework - I was paid according to how much I produced. Although, due in no small part to having had two spine operations, my body has gone to hell in a hand-basket at that time I was very fit, fast and strong. I got to a stage where I was earning a lot of money - however I also crossed a tax threshold where I was actually coming out with LESS money in my pocket than if I produced less and concomitantly got less gross pay to tax.

 

Consider this in relation to increasing the DRAM frequency - your pay - and the DRAM timings - your tax. At some point the tax you have to pay in timings exceeds the pay you get in increasing the DRAM frequency.

 

My advice is, forget what the rig you have should be able to do. Start off at the lowest DRAM frequency rating with the motherboard settings set to "auto" and gradually raise it seeing how that affects the adjustment the board makes to accommodate the change.

 

Forget "XMP profiles" which are based on a best case scenario; however, as I tried to show above, the assumptions made with regard to the rest of the hardware to actually be able to live up to them is outwith the control of the engineers at Corsair.

 

Sure you might get the DRAM to work with the higher frequency settings (your pay) but the price which is exacted with regard to the timings (your tax), i.e. the amount of time your memory subsystem spends doing nothing, could actually end up with you getting LESS performance.

[Ultima95]

With regard to memory "speed" it is a case of swings and roundabouts. If one looks at increasing the DRAM frequency at some point one has to increase the timings simply because of the DRAM latencies which have - individually - a minimum below which one just cannot go.

 

Another thing to consider - which I almost never see mentioned - is the actual distances on the motherboard the signals have to travel.

 

Signals have to travel the distance and return within a very narrow time frame and those signals have to reach the components and return in the right order. One main factor influencing this is distance. Another factor is the conductivity of the material and how that material's conductivity is influenced by temperature.

 

The effects of this are minuscule - until one starts increasing the frequency of the usage of a bus. At some point a limit is reached. A motherboard might be specified for a certain "speed" but this assumes that everything during the production process has gone absolutely perfectly - differences to be measured in atoms can make the difference between yea and nay.

 

There is of course a "bugger factor" which is the DRAM refresh instruction which can also collide with settings irrespective of the validity of those settings just due to the strobe effect - i.e. the refresh coincides with some instruction sent to the RAM or some instruction which was not received from the RAM which results in a BSOD because the RAM refresh happens and coincides at the level below the HAL. The refresh ALWAYS has precedence over anything else.

 

To increase the DRAM frequency beyond a certain point one has to increase the voltage and of course that just introduces more heat and it might not be enough to compensate for the other factors.

 

So with interacting computer components there comes a point where the "should be able to" intersects with the "will be able to".

 

No one component is to blame, it is the interaction of the components which has to be pretty close to perfect for the "should" and the "will" to coincide for the higher performance to be realised.

 

Scottie's famous admonition to Kirk should be borne in mind, "Ye canna change the laws of physics".

 

The DRAM timings are plain and simply instructions for components to do NOTHING for a certain period of time before they try to send a signal again. This is why I talked about swings and roundabouts with regard to "speed" at the beginning of the post.

 

Let me put this another way. Over thirty years ago I worked in a concrete factory doing piecework - I was paid according to how much I produced. Although, due in no small part to having had two spine operations, my body has gone to hell in a hand-basket at that time I was very fit, fast and strong. I got to a stage where I was earning a lot of money - however I also crossed a tax threshold where I was actually coming out with LESS money in my pocket than if I produced less and concomitantly got less gross pay to tax.

 

Consider this in relation to increasing the DRAM frequency - your pay - and the DRAM timings - your tax. At some point the tax you have to pay in timings exceeds the pay you get in increasing the DRAM frequency.

 

My advice is, forget what the rig you have should be able to do. Start off at the lowest DRAM frequency rating with the motherboard settings set to "auto" and gradually raise it seeing how that affects the adjustment the board makes to accommodate the change.

 

Forget "XMP profiles" which are based on a best case scenario; however, as I tried to show above, the assumptions made with regard to the rest of the hardware to actually be able to live up to them is outwith the control of the engineers at Corsair.

 

Sure you might get the DRAM to work with the higher frequency settings (your pay) but the price which is exacted with regard to the timings (your tax), i.e. the amount of time your memory subsystem spends doing nothing, could actually end up with you getting LESS performance.

 

Great post, I didn't know how the timings would affect the rest of the components.

 

But I wanted to answer this part:

 

My advice is, forget what the rig you have should be able to do. Start off at the lowest DRAM frequency rating with the motherboard settings set to "auto" and gradually raise it seeing how that affects the adjustment the board makes to accommodate the change.

 

In my case only works beyond the SPD 1333 if I keep the same voltages and timings, except for the first four timings. If I let the motherboard set the timings beyond the SPD standard.......... it wont boot at all, 3 beeps every time it tries to boot, back to BIOS button does nothing then, only the BIOS jumper reset the mess the automatic OC do.

 

As I commented before in my other post so far is working at 1600, but I don't know yet if the computer is stable.

[Nec_V20]

You will notice if you have set everything else in your BIOS to "auto" that your timings have gone up to ten or more as opposed to nine if you look at your individual RAM if you have kept the voltage to 1.5 Volts. So for an 83% increase from 1333 to 1600 you have incurred a penalty of 11% for every single value in the main timings.

 

You will also notice that the timings further down have gone even more into the toilet.

 

The only optimal "speed" you can do at 1.5V is 1333, that's your whack. Above that you have to bugger about with the voltage and really, ask yourself, do you want to do that?

 

Swings and roundabouts

[Nec_V20]

Great post, I didn't know how the timings would affect the rest of the components.

 

It is amazing how much the term "timings" has been mythologised whereby the term just simply means "Doing bugger all for the time specified".:biggrin:

[Ultima95]

There is no need to mess with the secondary timings. If your system is not stable at the advertized settings then you either have a bad set of memory or the MB BIOS is not adjusting them correctly.

 

If yu would like to replace the ram to rule out one or the other , then just use the link on the left to request an RMA.

 

 

Well, after blaming Intel for being unable to configure the timings correctly, at the end was a case of a bad module. It took time to troubleshoot, but the computer is perfectly stable with other kits (know good ones) and the one I had at the end went so bad that I couldn't boot any more, but up to that moment it was pretty ramdon.

 

I wonder if the OP also has the same problem, because the BIOS *is* able to set the secundary timings correctly after all (tried with another two sets of kits so far) and worked without issue -- it acepts the profile right away, no need to change any timings at all.

 

I am going for this kit instead CMZ16GX3M4A1600C9, works perfectly; checked (borrowed from anocther computer)

[Ultima95]

You will notice if you have set everything else in your BIOS to "auto" that your timings have gone up to ten or more as opposed to nine if you look at your individual RAM if you have kept the voltage to 1.5 Volts. So for an 83% increase from 1333 to 1600 you have incurred a penalty of 11% for every single value in the main timings.

 

You will also notice that the timings further down have gone even more into the toilet.

 

The only optimal "speed" you can do at 1.5V is 1333, that's your whack. Above that you have to bugger about with the voltage and really, ask yourself, do you want to do that?

 

Swings and roundabouts

 

I only get kits that work at 1.5v (XMP profile at that voltage) -- well at least with recent computers.

[RAM GUY]

I would suggest we try and replace the modules based on what you posted.

Please use the link on the left and request an RMA and we can replace them.