Optimal RAM choice for motherboard and overclocking ?

MiKu MiKu DJ

Honorable
Apr 27, 2013
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0
10,510
Hi to all!

I'm planning to build a PC for gaming (OC build, if possible depending on my budget) and "professional" Video Editing, I have some doubts about the tech specs of Memories in relation to the Motherboard and the possibility to overclock the system, that means the correlation between the best option for the whole build (CPU, MB, etc...) and the specifications of the Memory itsself, that's why I really need your point of view for the optimal choice I could effort.

I'm a beginner, I have never built a PC and something I could write down could be wrong or not clear, guide me trought the thread if I hadn't to understand some aspects of your replies. I created different threads about each part of the build because I have a lot of doubts and I wouldn't waste money for parts which are unnecessary or incompatible.

-https://it.pcpartpicker.com/list/8rW2jc
(prices in black, where not shown automatically, are taken from the lowest price I found on Amazon(.it) and ePrice(.it))

I'm more into Corsair products and I got the eyes on the new Dominator Platinum series:

http://www.corsair.com/en/dominator-platinum-series-32gb-2-x-16gb-ddr4-dram-3200mhz-c16-memory-kit-cmd32gx4m2c3200c16

Checking at the Tech Specs tab, I have doubts about:

-What's the SPD Speed in relation to the Tested Speed ?
2133 Mhz Vs. 3200 Mhz ?

-What's the SPD Latency in relation to the Tested Latency ?
15-15-15-36 Vs. 16-18-18-36 ?

My choice for a MB would be an Asus brand MB and my options could be:
-ASUS Maximus VIII Extreme
-ASUS Maximus VIII Formula

both MBs have:
-4 x DIMM, Max. 64GB, DDR4
-Dual Channel Memory Architecture
-Supports Intel Extreme Memory Profile (XMP)

On the Asus MB Specification tab there is a list of OC values. I think the OC values are the frequencies RAM could run in OC mode, is it correct ? I see that the only values without the OC tag is 2133 MHz, is it the base frequency RAM runs ? My conclusions are that the Dominator Platinum Memory kit (2*16 Gb) is compatible with the MB options (Extreme or Formula) and they could be overclocked up to 3200 Mhz due to the XMP profile. Am I wrong ? How does the XMP profile work ?

I chose a 2*16 Memory kit because the GPU I would like to purchase is the ASUS GeForce GTX 1080 8GB GDDR5X STRIX OC Gaming, and I heard the recommended amount of RAM is 16Gb, the extra RAM could be always usefull for any other applications (for the most video editing) and better overall performance. I'm for the 2*16 kit because the MBs can support up to 64GB and I could later purchaising another kit to maxing out RAM. And here I have another doubt. Is it a good choice using only two slots of four, or is it better a 4*8Gb Memory kit but using all the four slots ? I know that a Memory kit is build and projected to be used as a stand alone kit for better performance, is it correct ? Will there be any issues with two 2*16Gb kits installed of the same brand memory series (two 2*16Gb Dominator Platinum 3200Mhz kits) ? How should I install the kit, which slots have to be used for the first two RAM sticks ?

Another doubt is that the latest three memory series by Corsair:
-Vengeance LPX
-Vengeance LED
-Dominator Platinum

have all the same specs (at the same frequency for the same kit). Which is the real difference between them ?

Last question, for the build I have in mind, do I really need 32Gb 3200Mhz RAM ? Any other suggestions ?

Thank you all in advance!
 
Solution
(CL/(freq-in-MHZ) * 1000) = timing in ns

(19/4266)*1000)= 4.45ns
(14/3200)*1000)=4.37ns
(10/2400)*1000)=4.16ns

You can see that CAS has a more dramatic impact on true latency being the numerator.

Two slots is actually technically slightly better than using all four, but not enough to worry about. You can add another 2x8GB of RAM later, but there is a small chance the RAM won't be compatible, RAM is very, very picky about being paired together.

No, more than 16GB is pointless unless you're doing stuff with your RAM like RAM discs.
 

MiKu MiKu DJ

Honorable
Apr 27, 2013
24
0
10,510


Thank you! But... Where could I check the RAM CL ? Please, make a pratical example with the Corsair Dominator Platinum, as you could guess, I'm a beginner and I want to understand why. From the tech specs I can only see the SPD Latency and the Tested Latency with different numerical values, which is the CL ?

http://www.corsair.com/en/dominator-platinum-series-32g...

SPD Latency
15-15-15-36

Tested Latency
16-18-18-36

Which value should I use in the formula to get the timing of that specific RAM ? What do those numbers mean ?
Which is, in your opinion, the best 16Gb kit by Corsair ?

Thank you again!
 


The first number of timings is your CAS/CL - that is the number you'll use for calculating. This is the number of cycles the RAM goes through to respond. Regarding the info that corsair is giving you, just go with the actual numbers the stick shows for timing.
The larger number, the speed, is the speed at which a cycle is completed. So you can think of it as running
X cycles at X speed.

 
Solution