Question about RAM options

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I'm a newcomer to this forum, and an overclocking noob, so hi all!

I've just been looking at the sections on memory and CPU o/clocking, but can't quite get my head around ram with faster clock speed but higher CAS latency, versus slower RAM with lower latency. (I get it that CAS is measured in clock cycles, so it is also relative to clock speed, but I don't know how much weight to give latency, as it's only one aspect of overall RAM performance).

So I have a specific question based on my intended purchase as follows:
Asus ROG Maximus VI HERO Intel Z87 Socket 1150 motherboard
Intel Core i5 4670K.

Assuming I don't overclock, will there be any difference between the following 3 memory options - in terms of performance or stability?:

16GB (2x8GB) Corsair DDR3 Vengeance Pro Series Blue PC3-12800 (1600), Non-ECC Unbuffered, CAS 9-9-9-24, XMP, 1.5V
16GB (2x8GB) Corsair DDR3 Vengeance Pro Series Blue, PC3-14900 (1866), Non-ECC Unbuffered, CAS 9-10-9-27, XMP, 1.5V
16GB (2x8GB) Corsair DDR3 Vengeance Pro Series Silver, PC3-17066 (2133), Non-ECC Unbuffered, CAS 11-11-11-27, XMP, 1.5V

And if I did overclock, which would be the best of those options - firstly in terms of how suitable they are for overclocking in my configuration, and secondly in terms of performance and stability?

I appreciate that the real-world performance difference is unlikely to be dramatic, but on the other hand, there's only a small price difference between all 3 options.

TIA,

Michael...
 
Hi Michael

See http://forums.overclockers.co.uk/showthread.php?t=18590578

9/1866 = 0.0048231 is the 'fastest'.

Hi rjd,

Thanks for the reply. I figured one could divide one by the other to get a single figure, but that implies that performance is proportional to absolute latency. But latency is only one part of the total cycle, correct? So even though absolute latency might be equal, the faster clocked RAM is still going to be faster.

My underlying question might be about how much of an effect "x" nanoseconds of latency has on total performance. Or am I misunderstanding the situation?
 
Hi Michael

I believe that's covered by my EDIT:

'See post #7 & #8. If the 'lowest numbers' are close, it's best to go for the one with the highest frequency.'
 
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