Feldmarschall :
wdmfiber :
I'm saying the memory controller on the 3570k is better than the 2500k. Example: let say you bought 2400MHz ram. On a 2500k you'll likely only get it to 1866MHz. But on a 3570k you may get the same modules to 2133MHz. It's not an exact sicence, but generally you can go 2 "steps" higher with an Ivy Bridge CPU.
This forum member had ram booting at 2133 with a 3570k, but only managed 2000MHz with a 3770k(same ram). So that's variations in the controller, of the same family of CPU's.
http://www.tomshardware.co.uk/answers/id-1632978/3570k-memory-controller-3770k-issues.html#10546631
But in the end you want the fastest overall latency anyway. 1600MHz ram with 8-8-8 timings is usually alway fastest anyway. The latency is 10ns (nanoseconds). You have to look it up on a chart, but even 2133MHz ram at a fast 11-11-11 is slower.
The below ram is cas 7! That's crazy fast/arguably the best. 2500k/2600k/3570k/3770k... whatever CPU, this ram would be awesome to have in a PC.
http://www.newegg.com/Product/Product.aspx?Item=N82E16820231628
This is something totally different and i agree with lower latency...But you said that 2500k likelly won't even boot with 1866Mhz. I said that 2500k has nothing to do with it if motherboard will support. If mobo supports it, it will work. Do you agree with this or not?
I will not let being accused of not knowing parts of CPU and this to hang in mid air so OP would be scared to go over 1600Mhz if he want's.
I don't agree...
I can't explain it very good I guess. But the reviews for the fast MHz G.Skill Trident are filled with that exact problem. People buy the fast ram cause it's available(i guess) but it won't work in their PC's at the high advertised speed. G.Skill tech support must go mad with the huge number of RMA's.
Here are some excerpts from G.Skill resonses:
Manufacturer Response:
Dear Customer
...not all CPUs are natively capable of DDR3-1866...
...We can surely assist you in achieving the rated specifications. This memory kit is absolutely guaranteed for DDR3-2133 CL9, and it can be capable of more with a good CPU...
...We are sorry to hear you are having issues reaching the rated specifications of the memory. The memory does reach the advertised speeds if you have a CPU that can support it. The memory controller is embedded in the CPU, so the actual memory speed may vary due to the overclocking margin of the CPU....
...We can certainly clarify the confusion you may have. Intel does NOT support overclocking, so DDR3-1600...
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Those are just four. Almost all the OC'd ram on newegg has Manufacturer Responses, to bad reviews. They get taken down after a while, cause there get to be so many. No doubt it's bad for sales.
And to get at what your saying(I think). Some ppl do complain because the memory is "only" operating at 1333 or 1600, but that is the just the default speed and they need to set it for an OC.
Anyway, I have an Asus Z77 Deluxe board with an i7. My board supports ram up to 2600MHz OC. But if I bought some 2600 dimms, I know there is no way the controller in my CPU could handle it. I'd be lucky if it booted at 2000MHz.