Memory Sub Timings calculator

[neieus]

I have been reading about the different memory sub timings and was wondering does anyone know if a memory sub timing calculator exist? I'm aware that CPUZ provides some of that information already as well as the manufacture of the memory module for the top rated speed. So as an example my current memory has 11/11/11/31 for 2133 but what if I wanted to change the CL from 11 to 10... what would the other 3 sets of numbers need to be to insure it actually works right? The other sub timings I leave on auto so that my system can figure the rest out on its own.

 

[Pinhedd]

I have been reading about the different memory sub timings and was wondering does anyone know if a memory sub timing calculator exist? I'm aware that CPUZ provides some of that information already as well as the manufacture of the memory module for the top rated speed. So as an example my current memory has 11/11/11/31 for 2133 but what if I wanted to change the CL from 11 to 10... what would the other 3 sets of numbers need to be to insure it actually works right? The other sub timings I leave on auto so that my system can figure the rest out on its own.

You can leave them all on auto except for the three (or four) big ones. The firmware will calculate the secondary and tertiary timings during the SDRAM initialization.

 

[neieus]

That's the thing though how do I determine the main remaining 3?

 

[Pinhedd]

That's the thing though how do I determine the main remaining 3?

Those are the 3 or 4 that are included on the package. Eg, 11-11-11-31 or 9-11-10-28

 

[neieus]

That's the thing though how do I determine the main remaining 3?

Those are the 3 or 4 that are included on the package. Eg, 11-11-11-31 or 9-11-10-28

You misunderstand... I know what those numbers are on the package and I already have them set but let's say for example I wanted to change them to something different than what is listed on the package... How can I determine the right combination that actually works?

 

[Pinhedd]

That's the thing though how do I determine the main remaining 3?

Those are the 3 or 4 that are included on the package. Eg, 11-11-11-31 or 9-11-10-28

You misunderstand... I know what those numbers are on the package and I already have them set but let's say for example I wanted to change them to something different than what is listed on the package... How can I determine the right combination that actually works?

You can't determine that algorithmically. Those numbers are picked based on the performance characteristics of the integrated circuit. DRAM chip manufacturers such as Hynix, Samsung, Micron, and Toshiba manufacture their integrated circuits to specific JEDEC standards such as DDR3-2133L. DIMM manufacturers such as Corsair, G.Skill, Mushkin, and Kingston purchase these integrated circuits in bulk, separate out the best performing ones and assemble those onto a DIMM with tighter timings. For example, Hynix may sell a batch of of 1000 chips which are collectively tested to DDR3-2133K (the 11-11-11-31 that you mentioned), but a carefully tested subset of these chips may run at 10-10-10-28 if given a slight boost in voltage. Given that higher performing DRAM chips are more desirable there's generally very little overhead for tightening timings beyond that which is specified by the DIMM manufacturer.

You can attempt to boost the voltage and tighten the timings on your own but this is almost always an effort in futility.

 

[neieus]

OK that makes sense to me.

Thanks