XMP and multi-DIMMs per channel

[Gigo]

I am thinking of putting 2 x Corsair Dominator 1600MHz kits on to an X58 board (Asus P6T). I want to get the full 12GB supported by the board.

2 questions:

1) XMP & Multi-DIMMs per channel

I have seen several statements in mobo manuals and on the Intel site stating that you should only use one DIMM per channel if using XMP.

Am I correct in interpretting this as: if you have XMP turned on in your BIOS you should only use one DIMM per channel, but if you have it turned off you can have several.

Or do I need to avoid XMP memory all together if I want to use all of my DIMM slots?

2) Filling your DIMM slots

From a number of sources it seems that if I fill all of my DIMM slots that I will probably need to either downclock from 1600MHz to 1333MHz or, if I want to hit 1600MHz, raise the VDIMM and relax the timings.

Would the same hold true if I used 1333 native memory (i.e. would I either have to downclock it to 1066 or raise the VDIMM and relax timings), or should the mobo/chipset support 6 sticks at what is listed as it's stock rating?


Thanks

--Gigo

 

[Gigo]

The answer to my own questions...

Found a partial answer to my own questions. HardOcp have a video of fitting 6 sticks of Corsair Dominator 1600MHz and then getting it to run stable at nearly 1600MHz.

So, I guess this means my assumption about "turn off XMP and the 1 stick per channel limit goes away" is correct.

As is "plug, play and pray" for getting the memory up to full speed.

That just leaves my question about whether or not memory that is native to 1333 would run without downclockling or overvolting if all DIMM slots are used. Anyone know?

I think I already have enough information to go for the 1600s with confidence, but I am still curious as to the 1333 scenario.

--Gigo