What RAM would be better for my build?

Go with 1866MHz/CL9 as they're mostly the same price and are faster. Surely gaming won't see any considerable difference but faster speed would help in CPU OCing. 1866/9 Snipers or RJX, the one you can get cheaper

The corsair dominator platinum has a base clock speed of 2400MHz. But its a bit more expensive because of its high quality memory and its clock speed

Gskill is a good brand, the kit below should be good enough.

" I recommend 16 gb however the 8 gb kit below should be okay if you don't have many things running when gaming"

G.SKILL Ripjaws X Series 8GB (2 x 4GB) 240-Pin DDR3 SDRAM DDR3 1866 (PC3 14900) Desktop Memory Model F3-14900CL9D-8GBXL

You would need to use the XMP profile or manualy input the settings for the ram...

Below is a compatibility list for your motherboard, just click on the global button to see the list which includes higher clocked modules.

" Your cpu's memory controller is designed to run up to 1600 MHz @ 1.5 V however many use ram with higher voltage and frequencies which is safe"

" Most ddr 3 Ram will run @ 1333 MHz by default"

http://www.asus.com/Motherboards/Z97A/HelpDesk_QVL/

You simply enable XMP and select profile 1, XMP will set the sticks up for you

Why are specs for the haswell memory controller so conservative?

I know with Haswell E memory controller has been upgraded to 2133 for dd4


Haakenloob, I'm asking Tradesman1 the question because he is more knowledgeable about this topic than me...

To be honest, this appears to be be Intel sort of playing up the capabilities, not really but sort of....the Haswells are rated up to 1600, and 1600/9 is considered the base for 1600, next is where it gets a little complicated

Originally DDR3 was only specced to go to 1600 and once they laid out base specs for DDR3 they started on specs for DDR4 (JEDEC did), this was back about 2005 and the original specs called for 1600 to be around CL11. People wanted fast DRAM so that quasi norm of CL11 rapidly dropped to to 10 and then the current of 9, much as the DRAM manufacturers moved up the scale on DDR3 they released 1866 and 2133 sticks long before JEDEC ever released "Standards" for 1866 and 2133, and the manufactures continued setting their own 'standards' sort of for even faster DRAM like 2400, 2666, 2800, 2933, 3000, 31 and 3200 for which JEDEC has no standards published.

Now back to DDR4, in their thought process, believe they expected things to continue in the logical procession of go up a step in freq and also go up a step in CL (for a base), so we head back to 2005 and look at 1600/11 (their 'standard') then the logical progression to them was 1866/12 and 2133/13, thus we see the original releases of DDR4 with 2133 sticks running a 'base' of CL 13 and up through 15 more than likely. (I myself expect within months we'll see sticks with tighter CLs), but the initial release is sticking to outdated thinking)

Anyway, when we look at the Haswell CPUs while 'rated' to 1600, most all, even non Ks can easily run 1866 and many can run 2133 (and which to us is 2133 at CL11 or less), the new Intel 2011 CPUs they can fairly easily say rate to 2133 as DDR4 (today is at CL 13) which as far as a MC (memory controller) is concerned isn't much more than 1600/11 - not to mention Intel rates these CPUs as 1333/1600...2133 9and with DDR4 1333 is no longer) so Intel is sort of stretching things to fit new 'standards' while still relating to to what someone cconsiders normal opposed to abby-normal. IN short, from a performance standpoint compared to DDR3 the DDR4 at 2133/13 is very slow, with DDR3, 2133/11 is considered on the slow side for 2133

Very interesting, Thanks for the explanation...

No worries, really rather brief, but think it covers things

Absolutely!

DDR 4 with tighter timings sounds good!! I was about to build a Rig with a 8 core Haswell E however I decided to build a mini itx with 4790k instead.

I got the 1866 Corsair vengeance Pro because I wanted the low voltage and tight timings... I'm using these modules in my current rig because I'm still waiting for the Corsair graphite 380t and the ASUS Maximus VII Impact to complete the rig...

Good sticks, you should be happy w/ them