CPU-Z reports ram running at 530.7 Mhz instead of 667 Mhz

[Soilworker]

Hi

I have just finished a new build and CPU-Z reports my memory at 530.7Mhz. I have set the XMP profile in my EVGA SLI LE's bios and sure enough, it reads 1333Mhz (667Mhz). Another weird thing is the bios sets the command rate to 1T instead of 2T and tRC is 74? I've tried to set clock manually but no luck. What am I missing?

 

[mpilchfamily]

Well its better if its in 1T. You'll get better perfromance. As for PCU-z... if the bios says its running at 667 then thats what it is.

 

[Soilworker]

Alright then, I'll trust the bios, thx

 

[Zensal]

Maybe. Sometimes if you set your settings too aggressive, the bios will back it off automatically. I wouldn't be happy unless they matched. CPU-Z is a trusted program.

 

[Soilworker]

@ Zensal

Well I'm certainly not mad but let's say I'd like to solve the issue. I dont understand why my settings would be too agressive, after all I loaded the XMP profile which is what the memory is rated for. I know there are some reading problems for the SPD, CPU-Z reads the profile with 1T and the bios sets it at 2T. Would it be that my motherboard is still quite new on the market? I don't know what else to check. Would any other information be useful? With so few replies, am I even in the good section, or does this belong to the memory section?

 

[PurdueRy]

It's a function of your CPU speed. It appears you are overclocked. Therefore, you are going to have to set a divider. Right now its set to 2:8. You can change this divider to change the speed of the ram. You don't have direct control seperate from the CPU over the RAM clock speed. They are related.

 

[Soilworker]

Sorry for my newbness, how does it appear that I'm overclocked? I haven't touched anything cpu wise. As for the ratio of 2:8, I know, it's what I'm trying to say. My target in the bios is 1333 / 2:10 and when I boot up in to 7, I only get 2:8.

 

[Soilworker]

Hello everyone, I just read this in the stickied X58 memory guide over at EVGA forums. Is this the Uncore frequency my problem ( it's set to auto)? This is what leads me to think so. Considering the fact that I'm am completely new to this, I may have missunderstood the basic principle that is mentionned below. I didnt know I had to overclock in order to run my ram at it's rated spec.


The Core i7 architecture has what is called Uncore. The Uncore is the part of the processor that consists of the integrated memory controller and the L3 shared cache. A rule of thumb that must be remembered is that your Uncore frequency has to be at a minimum twice your memory frequency. The default Uncore frequency of a 920/940 processor is 2133 MHz, which is twice the default memory frequency of 1066 MHz. The 965 processor has a default Uncore frequency of 2666 MHz, which is twice the default memory frequency of 1333 MHz.

 

[PurdueRy]

Change the MCH strap setting you should see the effect of this on the CPU and memory clock in your BIOS.